One Finite Planet

EV Batteries Reference: Benefits & Battery Technologies.

First Published:

Table of Contents

Batteries for EVs have progressed:

  • From: very expensive even while delivering an impractical range.
  • To: Less expensive with an acceptable range.

Only now in 2022, are batteries showing signs they can soon enable EVs price competitive and range competitive. With the new world of EVs, comes a whole new world of understanding cars, with batteries at the centre. This page provides background, the rethink batteries bring, the different battery technologies, though to how to car for batteries, and who makes what.

Introduction.

What do I mean ‘Battery’? The origin of the name.

F150 Lightning – Can batteries power a 2022, Price competitive pickup?

I use the term battery to mean something acts as storage of electrical energy, and although I rarely state ‘rechargeable battery’ I when I use the term ‘battery’, it can be taken to mean ‘rechargeable battery’.

The term ‘battery’ has evolved over time, and my interpretation is that mobile phones and electric vehicles have made rechargeable batteries so common that we no longer need bother saying ‘rechargeable’ depending on the context.

Historically, and before modern ‘batteries’ existed, the word ‘battery’ meant ‘a number of similar articles‘. The word being independent of what these articles are. The word ‘battery’ still can be used for a ‘battery of guns’ or a ‘battery of tests’ or batteries of other things as with that original meaning, but without the ‘of something’ we now take ‘battery’ to mean a unit for storage of electricity, usually for chemical storage of electricity. Originally the electrical ‘battery’ was called a ‘battery of cells’ because they had a number of similar cells. This because shortened to ‘battery’ as battery of cells was used a lot, and now even when there is only one cell, such as a ‘AAA’ cell, we still call it a battery.

The original electric batteries were called ‘batteries of cells’ because they had a ‘number of similar articles‘ where each article was in 1749 as built by Benjamin Franklin, an electrical capacitor, and later built by Volta as a ‘battery’ of chemical cells, but there were always called ‘batteries’ because you needed lots of them. Now that we even call single cells ‘batteries’, which given that ‘battery’ originally meant ‘a number of similar articles‘, it is a little contradictory given the original meaning, and shows how meanings change. The meaning of ‘battery’ is still evolving as now the word ‘rechargeable’ is often implied .

Some people feel it is only a battery if the energy is stored as one or more chemical ‘cells’, but I would argue that it does not matter how the electrical energy is stored, to most people it is battery because of the function, not how it achieves that function. So in general use, anything that holds energy for later use as electricity, could be considered a battery. So even a capacitor can be considered a battery.

Batteries and Electric Car Basics.

This is a great video, really worth watching.

Single Use vs Rechargeable Batteries: For Vehicles, ‘battery’ means ‘rechargeable’.

Depending on context, the term ‘battery’ can be assumed to means ‘single use battery’ or ‘rechargeable battery’. If someone says “do you have AA batteries”, single use batteries are usually assumed unless it is specifically stated that the batteries are ‘rechargeable’. However, with mobile phones, automobiles and battery electric vehicles, battery is assumed to be ‘rechargeable’. We never say ‘rechargeable car battery’, or ‘rechargeable mobile phone battery’ because these batteries are always assumed to be ‘rechargeable’ batteries.

On this page, and all pages related to EVs, ‘battery’ is taken to mean ‘rechargeable battery’ unless specifically stated otherwise. In many ways, single use batteries have more in common with gasoline as as source of energy than with rechargeable batteries. With both gasoline and single use batteries, energy supplies are replenished by adding a new supply of the original chemicals. With (rechargeable) batteries, the battery is restored to the original state by putting energy back into the battery, and no new ingredients are required. The battery itself is ‘renewable’ rather than replaceable.

Batteries and the Price of Electric Vehicles.

There was a time when computers less powerful than what is today a low priced home computer filled rooms, cost millions of dollars and were something normal people imagined having at home. There was a time in the 1980s and early 1990s when mobile phones could cost $4,000 or $5,000 and normal people did not imagine ever owning one.

The bad news is electric vehicles are not about to go through that type of price crash. Just the batteries, which in a 2021 EV is around 50% of the price.

Chemical Energy: The power for all types of vehicle engines or motors in use.

All current vehicles are powered by chemical reactions. Internal combustion engines are powered by the heat from a chemical reaction between gasoline/petrol or diesel or hydrogen with oxygen, and electric vehicles are powered by electricity generated by a reaction between the chemicals inside the battery, or for hydrogen fuel cell vehicles, the chemical reaction between hydrogen and oxygen to produce electricity.

This is more fully explained here.

Recharging Vs Refuelling.

What Is The Difference?

All vehicles are powered by a chemical reaction, under the principle:

  • When Ingredients ‘react’ the result is ‘waste’ plus energy.

With an internal combustion engine, the ‘waste’ from the ‘reaction’ is mostly CO2 and water vapour, which are disposed of through the exhaust. With an battery vehicle, the ‘reaction’ is inside the battery, and the waste remains inside the battery.

Recharging is using energy to convert the waste back to the ingredients.

Refuelling is disposing of the ‘waste’, and replacing the supply of ingredients.

Could You ‘Recharge’ A Gasoline Engine? Technically, Yes.

In a gasoline engine, the main chemical reaction is:

gasoline + oxygen → CO2 + Water + energy(heat)
2 C8H18 + 25 O2 → 16 CO2 + 18 H2O ( simplified as per Wikipedia)

While there are some ‘burnt impurities’, and the heat is so intense that some nitrogen is also burnt, the components listed above are those that are needed for the engine to work.

In theory, if the tailpipe emissions of CO2 and water were retained, then instead of refuelling it would possible to add heat back into the ingredients, and thus run the equation in reverse, and thus ‘recharge’ back from ‘waste’ to ingredients:

CO2 + Water + energy -> gasoline(synthetic) + oxygen

This would result in a ‘sustainable’ internal combustion engine vehicle. Of course, there are some problems. This is not an easy reaction to run in reverse, and as internal combustion engines are very inefficient, so far more energy is required to reverse the reaction that the car was able to driving. All the heat energy will be needed to be ‘refuelled’ as well, even thought most of the heat from combustion was lost when driving. But if we captured the emissions from an internal combustion engine, then we could bring the car to an energy source and ‘recharge’ the emissions back into fuel and oxygen, thus operating like an inefficient electric vehicle.

This may sound far fetched, but the reaction:

CO2 + Water + energy -> fuel + oxygen

Is called photosynthesis, and although the direct fuel, sugar, takes a few conversation steps to make biofuel, this is the exact principle of the process of making biofuel.

Of course, ‘recharging’ in this case is extremely slow slow, and have this car wait while the recharging takes is impractical. So instead, the ‘recharging’ to make biofuel from CO2 water and energy is done outside the car, and the car is refuelled with biofuel made earlier. Or, in the case of fossil fuels, made way earlier.

Can You ‘Refuel‘ A Battery Electric Car? Yes, by battery swap.

Similarly, a lithium iron battery also runs a chemical reaction, only this is two half reactions at each side of the battery. Battery chemistries vary, but this is one example:

1)  LiCoO2 -> CoO2 + Li+ + e-(electrical energy)
2)  Li+ + 6C + e- -> LiC6

Where the Li+ electrolyte is in a solvent that can flow between cathode and anode. You will often see these formulas with a bi-directional arrow, because taking the electrical energy out makes the reaction go one way (discharge), but adding the electricity back makes the reaction goes the other way (recharge). At ‘recharge time’, instead of putting electrical energy back, it is technically possible to simply take out the CoO2 (Cobalt dioxide) and LiC6 (lithium graphite) as exhaust, refresh the electrolyte, and put in new LiCo2 (lithium cobalt dioxide) and C (graphite), replacing the chemicals as we are doing when refuelling a gasoline car. By replacing the chemicals, the car would be ready to go again without the time delay of recharging.

The problem with replacing the chemicals, refuelling the car by refuelling the battery, is that for every battery chemistry, there are different chemicals, which would mean refuelling points would need to be range of ‘fuels’ even more diverse than the different octane ratings we have for gasoline/petrol. Plus, not all chemical ingredients are in the convenient liquid form.

The solution is the battery swap. This requires there is an interface between battery and car which is purely electrical, and independent of the chemicals within the batter. There are still problems, primarily standardising battery form factors so not every vehicle needs it own individual battery swap is a benefit on road trips when full refill off power is needed quickly, but not as appealing as charging at home at night during the more common use of cars when not on road trips.

Hydrogen Cars: Half Way Solution?

Hydrogen cars are the “refuel’ solution with recharging taking place outside the car. The benefit of hydrogen over ‘biofuels’ is that hydrogen can be used in a fuel cell to allow for more electric motors for propulsion. The negative is that hydrogen is a very light gas, which cannot be liquefied at normal temperatures, resulting in the need for high compression which consumes significant energy.

Refuelling is Unstainable Without Recharging at Some Point.

In the end, there are good reasons why no one is going to actually wait while ‘recharging’ a gasoline fuelled vehicle.

The entire system with gasoline was conceived at a time when the very concept of ‘renewable’ appeared unnecessary. The approach was to never worry about ‘recharging’ the ingredients, because the supply of those ingredients was assumed to be effectively infinite, and the ability of the Earth to absorb the ‘waste’ exhaust gases was also assumed to be infinite.

If we now buy into sustainability and the idea that the ability of the Earth to absorb waste is finite, then we need to ‘recharge’ the chemicals we extract energy from as a similar annual rate to our use of the energy, whether we use fossil fuels, biofuels, hydrogen, or lithium based battery chemical reactions.

Nor is anyone going to refill the chemicals of a battery for a battery car, as batteries are designed for the battery to operate as a sealed unit, although battery swap of the entire battery does have some applications.

The ‘battery’ approach is to ingredients and ‘waste’ within a container, such that it an be either used to produce energy in the form of electricity on demand, or store electrical energy when connected to a supply.

Batteries vs Other Portable Power Sources(H2, Gas, Petrol, Diesel)

Disadvantage: The Size, Weight and Range or Operating Time.

The (Flawed / Outdated) Case For The Combustion Engine.

The size, weight and cost of a battery to provide the same total power is greater than a tank of fuel.

The advantages of batteries as pure efficient energy storage would win all the time, if it was not for their one Achilles heel: the size, weight and cost required to provide power for a long time.

However, as battery technologies improve, size, weight and cost reduce.

The video to the left explains the case against battery power as it stood at the date of the video. As I am updating this section in late 2021, there are already batteries with over 4x the energy density of those in the video, and energy density continues to improve, so size of this disadvantage decreases.

Given that the cost of the battery is in most cases soon offset by reduced running costs, the disadvantage becomes that only a battery of smaller size and/or weight is possible, reducing running time/range.

As mentioned in the video, the improved efficiency of electrical power can counter the disadvantage.

Advantages: Pure & Efficient Energy Storage.

Universal Fuel Source: Energy vs Chemical Power.

In theory you could make a ‘recharging system’ for an internal combustion engine as described above, but in practice, it will never happen.

When you are out of fuel for a diesel or gasoline engine, you need more of the exact chemicals the engine requires. You can’t just stumble upon gasoline or diesel fuel, and you can’t easily convert other things that are available into gasoline or diesel fuel.

Sunlight, wind, and even heat can be used to make electricity. Almost any form of energy can be converted into electricity and used to charge a battery. The source of the electricity has no impact on the design of the electric car. However, you can just use anything that will burn to power an internal combustion engine. Even the minor change from gasoline to diesel requires a significantly different engine. When gasoline supplies are disrupted, everything that depends on that specific liquid is disrupted.

Internal battery chemistry can change from car to car with no need to modify how electricity is supplied to the car. All of that battery technologies discussed below can be used with the exact same electric motors.

A battery vehicle can use any source for the energy. Not only is the mains electrical system that is normally used as the source of energy available at almost every dwelling in the developed world, but it is also possible to provide energy from solar or wind. Even in the most remote location, it is possible to generate electricity from natural sources without any need to locate specific chemicals. With enough time people could even hand crank a small amount of electricity. This allows for vehicles such as the Aptera, or the Lightyear One, that can travel normal commuter distances each day on a day’s solar energy alone.

Since batteries are recharged by energy, rather than the chemicals inside the battery that react to produce the energy when it is needed, how the battery stores energy can change, with no impact on refuelling. The reactions above are for ‘conventional’ lithium-cobalt-graphite batteries that have been used in most mobile phones and electric vehicles so far, but already different battery chemistries are being introduced, with phosphorous having already replaced cobalt in BYD batteries, and also being introduced by Panasonic.

Supply Security and Sovereignty.

Moving from requiring one specific chemical formulation for fuel, to requiring electrical energy, is moving depending on a very specify supply chain, to almost total flexibility.

A fossil fuelled engine can only be fuelled by fuel matching the specific chemical formulation for which it is designed. It becomes like the razors and blades business model, but where the car producers make the razors, and the fossil fuel industry makes the blades.

The consumer perspective is fuel prices, and the extent to which consumers end up funding some very questionable nations and some very rich companies, the national perspective security of supply.

Electricity is generic, and can be sourced from solar, or wind, or tidal forces, from hydro or from waves, as well as from any fossil fuel. Particularly with solar power, consumers can themselves take control of supply. Any of these sources, and more, can be used to produce electricity. If you have energy, you can produce electricity, while the gasoline or diesel required by an internal combustion engine can only be produced by an oil refinery, which in turn requires a specific far from universal resource. Oil rigs are as complex solar or wind farms, but instead of then using solar and wind resources that cannot be controlled by cartels, oils supplies depend not just on the equipment, but those who own the rights to supply.

Electricity grids can be very dependent on one way of generating of electricity, but while with fossil fuels there is only choice between nations that can produce oil, with electricity, not only can most countries produce much of their own electrical needs, but there are also so many ways or making electricity that they count not ever be controlled by one cartel.

When it comes to the energy to power cars, while cars that are powered by solar cells alone are not viable, the fact that cars spend over 90% of their time parked, enabled batteries charged by solar cells to play a major role in providing the energy for cars, and allows a percentage of consumers to control much of their own energy source, putting downward pressure on prices for everyone.

Many problems can disrupt the supply of fossil fuel, but the very nature of the electric grid means long term disruption of electrical supply to a wide area is far less likely, and there are even off the grid solutions.

Efficiency.

A typical car fuel tank holds between 50 (Toyota Corolla) and 90 litres (Mercedes GLS580 3 row SUV) which is between 13.21 and 23.77 US gallons. A Ford F150 pickup is available with 23 to 36 US gallons, or 90 to 136 litres. The energy density of gasoline is around 8.76 kWh/l so this means the capacity in litres, US gallons and kilowatt hours of tanks are as follows:

  • 2021 Toyota Corolla: 50 litres, 13.21 gallons, 438 kWh
  • 2021 Mercedes GLS580/ F150 base model: 90 litres, 23.77 US gallons, 788 kWh

Yet a Lucid Air, with a 115kWh battery pack can travel further on than the Toyota, Mercedes or F150.

There is further discussion on efficiency as it applies to cars in the topic “range”, but in typical applications, electric engines are at least 3x more efficient than combustion engines, resulting in more work done per unit of energy stored.

Safety.

You have probably heard of battery fires, the reason you hear is because battery vehicles are new, so it makes news, not because of the risk, which is low. It turns out if you store energy, then that energy could either explode or burn if not safely stored. In reality there are far more combustion engine fires every year per vehicle than electric battery fires, and the main reason fires and the potential for explosion with batteries is reduced, is the efficiency. As electric vehicles typically need 1/4 or even less, resulting in 1/4 of the problem. There is more to add to this topic.

Energy Density.

Units.

Energy can be expressed as joules (Watt seconds) or kilowatt hours. I kilowatt hour is 60(seconds)x60(minutes)x 1,000 watts = 3.6 MJ (3.6×106 Joules).

There are two measures of energy density:

Both are important, and although technically energy density should be called “specific energy”, when discussing batteries, the “energy density” discussed is most often weight.

Remembering there is no way to use more than around 25% of the energy from gasoline, so it being included in the table is not “like for like”.

Comparison.

Energy Density: here is how it compares with some batteries.

  • By Weight:
    • Gasoline: 13,138 Wh/kg (neutrium.net) (notes, great, but only only 25% accessible)
    • Innolith future battery : 1,000 Wh/kg (2024?).
    • Solid State: 450-500 Wh/kg (proposed July 2020)
    • NCA: 322 Wh/kg (Panasonic)
    • NMC: 230~250Wh/kg
    • LFP: 130~190Wh/kg
    • Nickel-metal hydride battery – 60 to 120 Wh/kg
    • Nickel-cadmium battery – 45 to 80 Wh/kg
    • Lead-acid battery – 30 to 50 Wh/kg
  • By Volume:

My plan is to add by volume data as I find it.

On this basis, a EV battery would weight around 10x what the equivalent amount of gasoline, and an 80kWhr battery = 80kWhr ÷ 250 Wh/kg = 320kg.

Also a 250kwh/kg battery is over 50x heavier than an equivalent tank of gasoline. (50×250=12,500)

Future.

When it comes to the energy density of the graphene battery, the numbers will surely be going to impress all the tech-savvy persons. In comparison to the good old lithium-ion batteries, graphene batteries will have a much higher energy density. This is because lithium-ion batteries tend to store up to 180 Wh per kilogram; on the other hand, graphene batteries are capable of storing up to 1000 Wh per kilogram. Therefore, now you can have a higher energy density battery pack in the same size as any other battery.

Graphene Battery Energy Density: Jan 2021

The most touted battery claiming a specific energy of 1,000 Wh/kg is the Innolith battery, but I have not seen any recent updates.

Our Next Energy: This company demonstrated a Tesla model S with a range of over 750 miles. This would suggest a battery with double the energy density of Tesla batteries, and thus around 500 Wh/kg (450), but it is hard to separate from the hype. The company has secured investment from BMW, Bill Gates and Jeff Bezos.

Several batteries claim 500 Wh/kg. E.g:

Battery Theory.

Terminology: Cathode, Anode, Electrode etc..

A note on terminology as it can be confusing, particularly the terms ‘cathode’ and ‘anode’ when discussing rechargeable batteries. The cathode is the terminal from which current flows, and the anode is where the current arrives. Since currents flow in the opposite direction during use of battery power or ‘discharge’ than current flows during ‘recharge’, each physical part of a rechargeable battery swaps roles. So the cathode during use, becomes the anode during recharge. This causes much confusion, and I have seen several videos and sites that get confused by this and think one side of the battery is always the ‘cathode’ and the other is always the ‘anode’, not realising this changes. Also note to make things even more confusing, electrons flow in the opposite direction to current. For these reasons, I will often use the clearer ‘positive electrode’ and ‘negative electrode’ in any explanations.

State of charge: How full is my battery?

With a fuel tank, either optical sensors or a ‘float’ can be used to measure how full the tank is, but how can anyone know the level of charge in a battery?

  • Answer: Mostly educated guesswork.

The only two times charge level can be certain, is when the battery is full and stops taking more charge, and when it is empty and provides no more charge. In between full an empty, software looks at the record of how much energy has been used since the battery was full, subtracts that from full capacity, and reports that number as the answer. So when your phone says the battery is now 50% full, they may be guess and not the real amount of charge.

Most batteries lose some voltage as they lose charge, allow updates to calculations. Unfortunately, the voltage also changes for other reasons, such as temperature and load, making working form voltage alone a problem. Getting readings of voltage under various conditions can can allow periodic corrections of the guess, which is why indicated battery level can suddenly jump.

No, the battery did not lose, for example, 20% in 1 minute. Software just realised its previous guess was wrong on the basis of battery voltage.

A problem is that reading battery voltage draws some power, and the voltage seen will depend on how much power is being drawn from the battery at the time. Accelerating an EV rapidly, and drawing lots of power, will cause voltage to drop temporarily. So voltage is not a perfect indicator.

Plus, the ideal battery would have the same voltage from almost full charged to fully empty, which makes reading voltage really challenging. The challenge of determining charge level varies with battery type, and in practice, the worse the battery type behaves, the easier the guessing gets.

LFP battery discharge curves.

Note, the curves shown here are all at constant temperature, and with constant power drain on the battery. In the real world of a car being driven, the load on the battery will also change the voltage as will temperature changes, putting ‘wobbles’ onto the readings.

As can be seen, from the graphs, LFP batteries have much flatter charge/discharge curves, which makes correcting calculations or ‘guesses’ harder. For this reason, some car makers recommend periodically fully charging LFP batteries in order to allow software to better determine level of charge.

Charge Time vs Refuel time.

Chemical batteries are limited in the speed they can absorb charge, but recharge points are also limited in the speed they can supply charge. Fuel tanks for gasoline and diesel vehicles can absorb fuel ‘instantly’, but the practical limits of hoses that carry fuel, and pumps, means it still takes some time to refuel.

For comparison consider diesel vehicles. There are special ‘high flow’ pumps for large trucks that can deliver fuel so fast that the fuel will go everywhere instead on just into the tank if these ‘high flow’ pumps are used with vehicles not specially designed. The tank can take fuel ‘instantly’, but the hose from the fuel filler to the tank can only manage a certain speed. Trucks can use a really big hose to handle a higher speed, but that is also limited by the maximum rate the fuel pump hose can handle. So there are three constraints:

  1. Gas/diesel pump speed.
  2. Hose from fuel filler point on car/truck to tank.
  3. Tank maximum fill speed (no problem with gasoline or diesel tanks)

With electrical vehicles, chemical batteries normally do have an effective limit on how fast ‘the tank can be filled’, but the other two limitations also apply:

  1. Charging Station maximum power rating.
  2. Car/truck connector and cabling to battery maximum power rating.
  3. Battery maximum ‘fill’ (recharge) speed.

This means that even with future battery technologies that do not limit battery recharge speed, refilling will still not be instant, just as refilling a large truck today is not instant. Currently the fastest chargers have a maximum power rating 350kw, so a 100kw/hr battery would need 100/350 hours or 17 minutes to recharge. The Hyundai Ioniq 5, one of the fastest charging vehicles of 2021, can recharge 75% of an 77.4kw/hr battery in 18 minutes, so just over half the maximum possible.

Actual battery charging rates are determined by battery technology in use. See below for battery charging rates for lithium ion batteries, the type of battery used in all EVs today(2021).

Battery charging times will, by 2025 if not earlier, be able to rival times for filling liquid fuelled vehicles, but practical limitations of getting the power to the car may mean infrastructure to deliver that power at the required rate will be rare.

The reality is that battery swapping is the true equivalent of refuelling, and recharging is a very different concept to refuelling.

Although rapid recharging can even soon match refuelling time, rapid charging should be considered something to avoid. It requires special infrastructure, and even if lower cost than fossil fuels, is inherently expensive compared to recharging while parked. Private cars spend 95% of their time parked, so it should be only very on rare occasions that rapid charging is needed.

Battery Life.

Batteries can be replaced, as shown on this video. While the battery structure with dedicated EVs is often currently integrated into the vehicle, and the replacement is specific to the vehicle, the process is simpler than replacing an engine in an internal combustion engine vehicle, and making 3rd party replacements should be easier.

One one hand, batteries are improving performance including lifespan so rapidly that already we are seeing batteries that may outlast the normal life of a motor vehicle. But on the other hand, batteries are improving so rapidly that batteries may also become obsolete before they should fail, and some batteries develop faults and other problems well before the end of their anticipated lifespan.

And as I said before, with batteries, it looks they’re going to start lasting way longer than the vehicles, which means you can amortize the cost of the battery over three vehicle lifetimes right, so where there were its going to land on batteries right now like no one has any idea. It’s really a strange time to be in this industry. And with the mineral resource issues and mining stories coming out about lithium extraction, your going to see more attention being put to battery technology. I think were going to see some interesting alternatives coming out here pretty quickly. Especially on the solid state side of things, you’re going to see some interesting breakthroughs.

Aptera CTO Nathan Armstrong.

The off the cuff remarks quoted above convey the contradiction that while batteries may now last longer than the car, they may be the first part of the car to be out of date. Fortunately, replacing the batteries can be practical, and as batteries improve, replacing them can result in a vehicle that becomes even better than when new. When batteries are replaced, the materials are valuable and recycling is possible.

Battery Care: Chemical Battery Charging.

Current Li Ion batteries, and most likely all future chemical batteries, can deteriorate over time as noted under ‘battery life’. Optimum battery life results when the following principles are all adhered to:

  1. Recharge and discharge currents must be limited to avoid causing elevated batteries temperatures.
  2. Rapid charging should be used sparingly.
  3. Batteries should rarely be discharged until capacity is exhausted.
  4. Batteries should rarely be charged to full capacity.

Consider mobile phones. Most of us break rule 4 almost every day by leaving our phones on charge overnight. Now phones can have software designed to maximise battery life, and detect a charge is an overnight charge so they can:

  • Use a slow charge provided there is sufficient time.
  • Pause the charge as soon as a ‘during the night’ level is reached.
  • Resume the charge as late as possible in the morning to ensure the phone is ready for the start of the next day, topped up to a level which still leaves a safety buffer.

But we not yet at the point where software can be fully aware of when to fully charge, and when to limit charging below the maximum.

Charging outside the schedule of overnight charging can assume special circumstances and rapidly charge, and allow rapid charging to proceed to full charge if the phone is left on charge.

There are articles that suggest rapid charging has no real impact on battery life, but full analysis always reveals that the increase temperatures that result from increased current do reduce battery life, and the only question is to whether the convenience justifies the impact. There is no doubt rapid charging is useful, the main care requirement is to limit rapid charging to when it is needed. With a relatively low cost mobile phone battery in phone that will be obsolete in perhaps 3 years, it matters far less than with a high cost EV battery in vehicle that still has value as a used vehicle many years after initial purchase. The average age of a car, even in the US, is around 12 years.

Some phones (e.g. Apple) do have software to try to avoid bad charging practices, but this is nowhere near as important with a phone as with a car.

Li Ion (Lithium Ion): The batteries of today (1998-2022?).

Overview.

At the time of writing, basically all EVs in the 21st century have had lithium ion batteries.

Despite first being developed back 1970, mass manufacture of any of the different types of lithium ion batteries is relatively recent. The first commercial battery products did not appear until 1991. If you are old enough to recall older mobile phones had first nickel cadmium batteries (invented in 1899), and then nickel metal hydride batteries, with both of these older battery types having a ‘memory effect’.

Recharging Lithium Ion Batteries.

Charge Rates.

Every battery has a maximum power that it can supply when proving power, and a maximum power it can absorb when charging. Generally speaking, the main focus is on the maximum power absorbed during recharge, as there are many situations where it is desired to charge the battery at the maximum possible rate, and few where it is desired to discharge at the maximum rate. Any car that can discharge its batteries in just 10 minutes is either attempting some form of speed record, or simply does not have enough battery life. The challenge is recharge speeds.

Batteries can now handle all the recharge speed we need. For example, CATL recently announced their Qilin batteries, to be mass produced now from December 2022, can be charged from 10% to 80% in 10 minutes, and stated they have future batteries that will be able to be charged from 10% to 80% in 5 minutes.

Now the question is how long will it take to have recharge stations that can charge batteries that fast.

The Lithium Iron Charging Curve, and the 10% to 80% (or similar).

Three are two ways that charging speed is indicated:

  • A maximum charging speed.
  • Charging time between a lower and upper limit.

While the maximum charging speed does reveal an upper limit to charging speed, this speed may never, or vary rarely, achieved. This is because the maximum charge rate for a battery varies according to how charged the battery is at that time, as well as the battery temperature.

Most batteries will accept charge 5x faster or more, at around 50% of full charge, than they will at 95% of full charge.

Charging only up to the point where charging slows, is advisable for both battery life in the long term, and fastest charging when on road trips.

Charging speeds and pack size: when all else is equal, a bigger pack add range faster.

Those speeds announced for 2023 represent a breakthrough, and in 2022, the fastest time for 10% to 80% is close to 20 minutes, and many typically cars will take around 40 minutes. Note that this percentage recharge time is per individual cell. With good batteries design, any number of cells can all be charged in parallel as this same speed, so no matter how large the battery, the same, or almost the same, total charging time can still apply. This means a larger battery with more cells not only provides more driving range, it can also store energy at a faster rate. Consider a car with a 50kWh “Kirin” battery, with an consumption rate of 100 w/km at 60km/h. This car can travel 350 km at 60 km/h using the charge available between 10% and 80% of that battery, and recharge the energy consumed in 10 minutes. Now consider a car with a 100kWh “Kirin” battery and the same rate of consumption. This second car will only drop the battery level from an initial 80% down to 45%, and could in theory possibly then recharge from 45% to 80% in just 5 minutes. The time to provide charge for the same distance halved, without any other change beyond increasing battery capacity.

Cobalt Lithium Ion: Since 1970 (NCA, NMC)

“Ternary Batteries”.

History

Electric vehicles so far have mostly used lithium ion cobalt oxide ion batteries (LiCoO2) as described here and first developed in the 1970s. NCA batteries use Aluminium in place of the Manganese used in MMC batteries, but both also use Nickel and Cobalt in addition to lithium. Lithium is highly reactive which would make significant amounts of pure lithium dangerous, so cobalt is combined with lithium to form LiCoO2 as a container to hold the lithium more safely in a less chemically active form. Cobalt is not rare, but cobalt in the form that is lowest cost to extract is found almost exclusively in the Congo, creating a supply chain risks, and at times as much of 10% of that Cobalt being mined, has been mined using unsafe practices. In batteries with cobalt, the cobalt becomes the main factor in the cost of the battery.

Note that with ternary batteries, limiting charging to 80% for normal use, as discussed in “battery care” is recommended.

NCA: LiNiCoAlO2, Lithium Nickel Cobalt Aluminium Oxide Batteries.

The ternary chemistry used by Tesla and produced by Panasonic. Historically the highest density lithium battery, but also the battery presenting the greatest risk of fire.

NMC:  LiNixMnyCozO2, Lithium Nickel Manganese Cobalt Oxide Batteries.

The most popular batteries for EVs until 2021 for all but Tesla, and still most popular outside China in 2022. The fire risk, and energy density, is just slightly below that of NCA batteries.

Phosphorous: In passenger EVs since 2020 (LFP).

Lithium ion phosphate batteries (LiFePO4), are an alternative to using cobalt that reduces battery cost and results in a safer battery, with significantly lower fire risk. LFP batteries also outlast ternary batteries.

Historically, despite being less expensive and longer life, lithium ion phosphate batteries (LiFePO4) have had lower energy density than cobalt based batteries, which limited their use to busses and larger vehicles. However, several companies now have solutions to the energy density, which allows a price, safety and lifespan breakthrough from lithium phosphate batteries such as the BYD blade battery. LFP batteries may takeover from the current at the time of writing champions: NCA and NMC.

LFP batteries are used now almost exclusively in BYD vehicles, and to some extent in other Chinese brands and some Teslas. Teslas with LFP batteries do not have the “set limit 90%” option present with their NCA batteries.

LMFP: Lithium manganese Iron Phosphate.

Adding manganese, which is very low cost, reduces the amount of lithium required, and so reduces battery cost while at the same time increasing cell voltage and thus increasing density. They have been lifecycle limitation in the past with LMFP, however these are reported to have been solved.

Chinese media is reporting that CATL will mass produce lithium manganese iron phosphate (LMFP or LFMP) batteries already this year, on track with the company’s roadmap.

Adding manganese to the popular LFP formula increases the voltage and energy density of the battery cells, without a noticeable cost increase, since manganese is particularly cheap. However, I’m curious to see the impact of the voltage increase on the cycle life.

CATL will soon mass produce LMFP batteries

CATL’s LMFP goals

  • Gravimetric energy density: 210-230 Wh/kg
  • Volumetric energy density: 450-500 Wh/L

Considering a GCTP (gravimetric cell to pack) ratio of 90 % and a VCTP (volume cell to pack) ratio of 72 % of a module-less CTP battery, at the pack level we can reach 207 Wh/kg and 360 Wh/L.

It seems that most viable improvements to the energy density of the LFP chemistry will be made either by adding silicon to the anode or manganese to the cathode.

Anyway, some battery cell makers such as BYD, Gotion High-Tech, Sunwoda and Eve Energy are also testing LMFP batteries and providing sample units to automakers.

With LFP, LMFP, LNMO and sodium-ion we are starting to have plenty of cobalt-free battery chemistries to power the electric transportation revolution.

CATL will soon mass produce LMFP batteries

Links:

Lithium Carbon.

So far too small for EVs, and for mopeds and scooters.

Battery Technology Alternatives: Beyond Lithium Iron

(this section updated as new data emerges)

The benefit of all batteries being charged by electricity and output electricity, is that how batteries work internally can be changed with no impact on the infrastructure to recharge. This means that what we have now is only a starting point, and there are many potential improvements to charging times, cost, lifespan, safety and environmental impact still to come.

If you had a million dollars to invest in a battery company, right like right now where would you put your money, right, like it’s changing so quickly and every six months there is a new technology it doesn’t quite make it to market but you know it threatens to kind of like you know change the whole industry again, um so battery technology is a really weird one, right, like we have these lithium cells so they’re pretty good um five years from now they’re going to be way better different chemistry 10 years from now something different again so we are trying to be king of battery agonistic.

Aptera CTO Nathan Armstrong.

Sodium. 2023.

The press release from CATL, the worlds largest battery supplier for EVs:

Based on a series of innovations in the chemistry system, CATL’s first generation of sodium-ion batteries has the advantages of high-energy density, fast-charging capability, excellent thermal stability, great low-temperature performance and high-integration efficiency, among others.

The energy density of CATL’s sodium-ion battery cell can achieve up to 160Wh/kg, and the battery can charge in 15 minutes to 80% SOC at room temperature.

Moreover, in a low-temperature environment of -20°C, the sodium-ion battery has a capacity retention rate of more than 90%, and its system integration efficiency can reach more than 80%.

The sodium-ion batteries’ thermal stability exceeds the national safety requirements for traction batteries. The first generation of sodium-ion batteries can be used in various transportation electrification scenarios, especially in regions with extremely low temperatures, where its outstanding advantages become obvious. Also, it can be flexibly adapted to the application needs of all scenarios in the energy storage field.

The next generation of sodium-ion batteries’ energy density development target is to exceed 200Wh/kg.

At the event, Dr. Qisen Huang, deputy dean of the CATL Research Institute, said that sodium-ion battery manufacturing is perfectly compatible with the lithium-ion battery production equipment and processes, and the production lines can be rapidly switched to achieve a high-production capacity.

As of now, CATL has started its industrial deployment of sodium-ion batteries, and plans to form a basic industrial chain by 2023. CATL invites upstream suppliers and downstream customers, as well as research institutions to jointly accelerate the promotion and development of sodium-ion batteries.

CATL via PushEvs.

Advantages: (from clean technica)

  • No dependence or use of cobalt, lithium, copper, or graphite.
  • Patented zero-volt safe transport and storage.
  • Low cost with the total cost of ownership compared with lead-acid batteries with the potential for more cost reductions.
  • Uses existing lithium-ion manufacturing infrastructure which makes it scalable. Also, the company noted that it’s already been proven with several of its commercial manufacturing partners.
  • Its energy density is also on par with lithium-ion phosphate and has a wider operating temperature range of -30℃ to +60℃.
  • It also has fast charge and discharge capabilities.
Just have a think: March 2022.

Graphene: Future (September 2023?).

Although originally observed in electron microscopes in 1962 as occurring on supportive metal surfaces, graphene isolated and fully analysed for the first time in 2004 by Andre Geim and Konstantin Novoselov at the University of Manchester. This resulted in a Nobel Prize just 6 years later in 2010. Remember it took 16 years from Albert Einstein’s ‘miracle year’ of discoveries in 1905 to his Nobel prize in 1921, so it is clear this work was quickly recognised as a big deal.

Graphene based batteries hold promises of ‘instant charging’ combined with:

The rapid charging isn’t the only selling point. In the lab, NanoGraf says its graphene batteries show a 50 percent increase in run time compared to conventional lithium-ion ones, a 25 percent drop in carbon footprint, and half of weight needed to provide the same output.

Futurism.com

To date, graphene is the strongest mineral ever discovered, with 40 times the strength of diamond. It is more effective as a conductor of heat and electricity than graphite. … Graphene is capable of transferring electricity 140 times faster than lithium, while being 100 times lighter than aluminium. This means it could increase the power density of a standard Li-ion battery by 45%.

Mining Technology.

GAC, a subsidiary of Chinese state owned GAIC, has announcedThe batteries will be installed in the first vehicle from September[2021]”, which would be the 1 year anniversary of the joint venture project for GAC.

Solid State Batteries: Future (VW plans for 2024-2025)

Introduction

Solid state batteries promise far higher energy density than current electrolyte lithium ion batteries, almost instant recharging, lower costs, and can be extremely durable. Some project it will take 10 years for them to take over, but a joint venture between VW group and QuantumScape plans for volume production by 2024-2025, a similar time from to Solid Power. Independent engineering analysis by Cleanerwatt and Matt Ferrel (undecided) do believe these timeframes. CATL, Panasonic/Toyota BYD all have too much at risk and too much engineering not to also be there if solid state does reach market by that time.

QuantumScape is developing what many consider the Holy Grail of electric car batteries: a highly-efficient, long-lasting, long-range, fast-charging electric car battery cell.

The battery startup achieves this by replacing* the liquid electrolyte that regulates the flow of current with a solid electrolyte.

The polymer separator used in conventional lithium-ion batteries is substituted with a solid-state ceramic separator, QuantumScape says. As a result, the less-efficient carbon or carbon-silicon anode is replaced with an anode of pure metallic lithium.

Forbes: Feb 2021.

Silicon Anodes: A Lithium battery upgrade: 2024.

Another proposed advance is the use of silicon anodes (positive terminal) to improve energy density.

Silicon anodes are famous for their energy density, which is 10 times greater than the graphite anodes most often used in today’s commercial lithium ion batteries. On the other hand, silicon anodes are infamous for how they expand and contract as the battery charges and discharges, and for how they degrade with liquid electrolytes. These challenges have kept all-silicon anodes out of commercial lithium ion batteries despite the tantalizing energy density. The new work published in Science provides a promising path forward for all-silicon-anodes, thanks to the right electrolyte.

A New Solid-state Battery Surprises the Researchers Who Created It

Aluminium ion and Graphene: Future (Coin cells 2021, Automotive 2024-2025).

Batteries do not have to use lithium as the electron donor metal. Lithium is the lightest metal, and with the smallest size atom, but lithium atoms only have a single outer shell electron per atom, and thus only allow a +1 charge. Aluminium, although a larger and heavier atom, has 3 outer shell electrons, not one, and this gives aluminium the potential for a +3 charge, which it turns out can result in even greater energy density than with lithium. Plus lithium is so reactive, the batteries are normally made from lithium compounds, rather than lithium metal.

There are a variety of projects to deliver aluminium batteries, eg:

Graphenemg: Aluminium/Graphene batteries which can charge 20 to 60 times faster than lithium ion batteries.

GMG plans to bring graphene aluminum-ion coin cells to market late this year or early next year, with automotive pouch cells planned to roll out in early 2024.

Based on breakthrough technology from the University of Queensland’s (UQ) Australian Institute for Bioengineering and Nanotechnology, the battery cells use nanotechnology to insert aluminum atoms inside tiny perforations in graphene planes.

The GMG technology drops aluminum atoms into perforations in graphene.
The Graphene Manufacturing Group’s aluminum-ion technology can charge an iPhone in less than 10 … [+] GRAPHENE MANUFACTURING GROUP

Testing by peer-reviewed specialist publication Advanced Functional Materials publication concluded the cells had “outstanding high-rate performance (149 mAh g−1 at 5 A g−1), surpassing all previously reported AIB cathode materials”.

Forbes: 2021 May 15 (worth reading the article)

Supercapacitors and Ultracapacitors. (nothing scheduled to replace batteries).

Capacitors could also be used as the ultimate ‘solid state’ battery, simply storing a charge using electrostatic attraction. Although there is significant work on supercapacitors for use in EVs, and supercapacitors do function in some ways like a battery, the role they are currently ‘auditioning for’ is to augment the ability of a battery a battery to deliver extremely high currents instantly. If instead of feeding motors directly from a battery, the battery feeds a capacitor that in turn feeds power to the motor, then the system can deliver brief periods of peak current beyond what the battery can deliver. This role, not of being the primary battery, is what is being proposed at this time.

Companies involved include SkeletonTech.

Sulphur (2024 at earliest?)

German battery startup Theion is promising a new sulfur battery technology that could help mainstream electric cars offer 900 miles of range on a single charge. The best part? Compared to li-ion tech, sulfur is cheap.

New Sulfur Battery Promises 300% More EV Range

Lithium Metal (No date for commercial product)

This is a variation on the lithium ion batter as:

Lithium metal is one of the best candidates to replace graphite as an anode (positive terminal) material thanks to its high theoretical capacity. The problem is that batteries using lithium metal anodes currently have poor cycle life.

However, thanks to a new non-flammable dual-anion ionic liquid electrolyte this could soon change.

Push Evs 25th August, 2021

Sion Batteries.

see because the current population is clearly greater than

Al Air. (No products scheduled to replace rechargeable batteries)

In addition to Aluminium ion batteries where aluminium replaces the lithium, there are also aluminium air batteries. However, these batteries are, so far, not rechargeable and thus not a contender in the same way as other batteries technologies discussed here.

EV Battery Care.

Why?

Mobile phone batteries have similar chemistry to EV batteries (typically these are ternary batteries with cobalt), and we don’t limit their charging to 80%, so why bother with car batteries? The two main reasons are:

  • ev batteries are a much bigger investments.
  • cars have a longer life than mobile phones, so batteries need to last longer.

If we paid thousands of dollars for our mobile phone battery, then we would look after it far more.

Ternary batteries.

Note that these batteries require care charging above 80%, and should only be charged above 90% on rare occasions for maximum battery life. Long term storage should ideally be at 50%. Here is an article on the impact of different charging patterns, but note this data only applies to “ternary” Nickel/Cobalt batteries, which at the time of writing are almost the only batteries in some markets, but it won’t stay that way.

LFP Batteries.

LFP battery cells use a lower voltage around 85% of that of ternary battery cells, and as the battery voltage plays a role in battery degradation, and a fully charged LFP battery has a lower cell voltage, the requirement to limit charging is far less significant. Further, a LFP battery has around 3x the maximum life as a ternary battery, so even if treated with less caution, should still last longer. However, some argue that to get that full 3x extra life, LFP batteries should be treated just as carefully, while others argue the same chemical properties that result in LFP being a significantly lower fire risk, also means there is significantly less degradation when fully charged.

Battery Makers.

Car Brands.

So far, only BYD from China makes their own battery cells. Even Tesla, who makes battery packs from battery cells from Panasonic and CATL, does not yet make their own batteries. This may change, particularly with major brands would would see a huge part of their revenue go to battery suppliers.

VW.

Are VW looking at following in the footsteps of BYD?

With intial capacity of 40 GW, no, there are not on the road to being a BYD. Well, not yet.

Market Shares.

2202 H2.

CNEV Post: Not full quarter results yet, but still significant.

2022 H1.

Global EV Battery Shipment – January-May 2021:

If we take a look at the year-to-date numbers, it turns out that CATL (22.1 GWh) maintained its first place, but it’s only 0.4 GWh ahead of LG Energy Solution (2.7 GWh). The combined market share of those two manufacturers is 53.7%, which means that every second xEV on the planet is equipped with CATL or LGES batteries.

CATL clearly benefits from very high sales in China (including LFP deal with Tesla) and several global  contracts, while LG Energy Solution got a boost from the deal with Tesla in China and massive expansion globally.

Inside EVs May 2021

Panasonic, with 13 GWh, is not only behind the leaders, but its growth rate is below 74%, which is a worrying sign. Market Shares are as of May 2021.

  1. CATL – 22.1 GWh (up 300%) with 27.1% share.
  2. LG Chem’s LG Energy Solution – 21.7 GWh (up 184%) with 26.6% share
  3. Panasonic – 13.0 GWh (up 74%) with 16.0% share
  4. BYD – 5.5 GWh (up 235%)
  5. Samsung SDI – 4.6 GWh (up 106%)
  6. SK Innovation – 3.8 GWh (up 154%)
  7. CALB – 2.5 GWh (up 418%)
  8. Envision AESC – 1.6 GWh (up 11%)
  9. Guoxuan – 1.4 GWh (up 336%)
  10. PEVE – 1.0 GWh (up 43%)
    other – 4.3 GWh (up 235%)
    Total – 81.6 GWh (up 169%)

CATL: The worlds largest battery maker.

CATL is moving further ahead of rivals, particularly with the Qilin battery, available in LFP and ternary batteries, and supplies both to Tesla.

LG Chem: Battling some challenges.

LG chem is limited by having had problems with battery fires with both the Chevrolet Bolt and Hyundai Kona, plus not having an LFP battery as of 2022.

Panasonic: The Initial supplier to Tesla.

Panasonic were for a long time Tesla’s only battery partner, however Tesla ramping up in China has seen a closer relationship with CATL, plus Panasonic does not yet offer LFP batteries as of 2022.

BYD: The Blade battery.

BYD is the only battery maker that is also a car maker. BYD has gone stronger than anyone with LFP, with the their blade battery largely regarded as the safest battery on the market as of 2019-2022.

Note that BYD LFP batteries have effective charge rates that are close maintaining their peak charge rate: How does BYD make the blade battery charge faster than the ternary lithium battery

GAC

Prologium.

Supplier to Vinfast and Mercedes, with upcoming solid state batteries.

Gotion High Tech (VW)

S Volt (solid State)

Upcoming Products.

Under battery technologies below, there are several new products and their proposed timelines. However, this is not car companies announcing products. I will add links here to cars with new tech, but it may take time:

Tesla 4680 Battery.

WeLion: NIO expected to get small batch of 150-kWh semi-solid-state batteries from WeLion in September

Conclusion.

The battery journey is still at an early stage. Right now, the cost of batteries puts EVs at a cost disadvantage to conventional cars, but that disadvantage is evaporating rapidly as shown by the quite competitive F150 lightning recently announced. By 2025, there will be a cost competitive EV for almost all new vehicle market segments.

However, 2025 is not the end of the line. EVs will continue getting less expensive for years to come, just as PCs did for decades.


Updates.

Articles found after posting.

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