In this post, I want to talk about the "Batteries" in Battery Electric Vehicles, or BEV's. Some members on this forum have expressed concerns about them, such as how long will they last, does charging degrade them, and other concerns. All completely legit concerns I'll try to address. One of the main reasons for some of the concern is, they are not only the powersource that moves the wheels and powers the car, but they are the most expensive component in the BEV, comprising anywhere from $15,000 to $30,000 of the cost of the vehicle.

So simply, a Battery Electric Vehicle is comprised of the frame, body, motor(s), of course battery pack. Depending on the manufacturer, battery packs can be pouch style, Cylindrical, they can be installed in modules, or as part of a structural pack where the pack is not serviceable (the whole pack is replaced). There are several types of battery chemistries, the two main ones are Lithium-ion and Lithium Iron Phosphate. Below is a chart showing the differing battery chemistries:



I'm not going to get into the pros and cons of which battery chemistry is better, pros and cons of pack styles etc. But what I'm going to talk about is the most important part of battery packs, and that's the Battery Management System (BMS). In short, the BMS is responsible for:

• Monitoring the battery
• Providing battery protection
• Estimating the battery’s operational state
• Continually optimizing battery performance
• Reporting operational status to external devices

To try and explain everything the BMS does would take up pages, but in summary, it manages the voltage, discharge rate, protects it during charging, and performs thermal management, keeping the battery pack at optimal temperatures at all times. This is key to battery pack life because excess heat causes wear and tear and premature failure of the battery.

How long does a battery pack in a car like a Tela last? According to several articles I've read, 300,000 to 500,000 miles. Motor Trend has an article on this:

https://www.motortrend.com/features/...-battery-last/

A properly maintained and managed Lithium-ion battery pack will last 1500 full charge/discharge cycles. That would give most people 15 to 16 years before the battery pack needs replacing. For more information on the longevity of EV battery packs, check the link out below

https://www.autotrader.com/car-tips/...batteries-last

 

Now I'm going to mention the different types of EV battery cells:

There are three basic types of battery cells used in electric vehicles: Cylindrical Cells, Prismatic Cells, and Pouch Cells. Coin cells also exist, although these are currently restricted to research and development for testing purposes and haven’t been used in EVs commercially

1. Cylindrical Cells

The most commonly used format, cylindrical cells are, like the name implies, self-contained in a cylindrical casing that gives them resistance against mechanical shocks – very similar to your typical household AA or AAA alkaline batteries.

Because of how long this format has been used, cylindrical cells are the most cost-efficient and easy to manufacture. That said, cylindrical cells can be somewhat limited in their power output, which is why EVs with smaller batteries often use prismatic or pouch cells.

2. Prismatic Cells

Unlike cylindrical cells, which are fairly small (about the size of a AA battery), prismatic cells can be up to 20 to 100 times larger. Because they use less material for the casing, prismatic cells can store more energy and deliver higher power, while also managing heat better than cylindrical cells.

While less popular than cylindrical cells, their use has been steadily growing and they may take over a large share of the market in the coming years.

3. Pouch Cells

As their name suggests, pouch cells are encased in a soft plastic casing, making them very efficient in terms of space usage. That said, their fragile casing means they usually require additional protection to prevent mechanical damage to the cells

https://www.laserax.com/blog/ev-battery-cell-types

 

The charging cycle tech is a science in it's own right. IMO

In theory, perfect charging will never degrade the chemistry of the battery.
However, in reality, there is always degradation as everything tends to break down over time to a lower state.

It's impressive the gains they have made in this area.

I'll just be honest and go ahead and say it.
Since I would be in the used car market for in the future when the time comes to switch to EV, longevity matters.

Yeah, I see they have drastically improved charge cycles and can go 300k but it's the Age of the Batteries that concerns people buying second hand.
I wish they would always make the battery packs in serviceable cells like Toyota does on the Hybrids.

Looking forward to what they come up with next.

 

The prices of batteries have gone down drastically and will continue to do so. Back in the day a Prius replacement battery pack was $10K. Today it's under $2000. By the time these battery packs degrade, which is in the next 10 or 15 years, you will be able to get a replacement battery pack for cheap. I watched a guy do a Model S battery replacement, took him under an hour

 

My neighbor's 2018ish Accord hybrid needed a battery replacement and the dealer wanted to charge him $8K for it. He opted to sell it and his wife's older CRV and got a 3P and MYLR

 

They don't warranty their batteries for 8 years? He could have gone third party and got it done under $2k, but he made the right decision in my very biased opinion

 

No idea on the warranty. Wouldn't be the first time a dealer tried to get out of warranty work. He's much happier with the new stable though

 

When they can get the price down to $3-5k for a replacement battery INSTALLED, I believe it will change the car industry.

Basically the cost of a donor engine install or transmission rebuild on an older used ICE car.

Preferribly an oem battery and not aftermarket mystery battery. Lol

Then back in business for more miles.

On the Road Again

 

Thanks for that pick me up! The costs of EV battery packs has been steadily declining:

FOTW #1272, January 9, 2023: Electric Vehicle Battery Pack Costs in 2022 Are Nearly 90% Lower than in 2008, according to DOE Estimates

The Department of Energy’s (DOE’s) Vehicle Technologies Office estimates the cost of an electric vehicle lithium-ion battery pack declined 89% between 2008 and 2022 (using 2022 constant dollars). The 2022 estimate is $153/kWh on a usable-energy basis for production at scale of at least 100,000 units per year. That compares to $1,355/kWh in 2008. The decline in cost is due to improvements in battery technologies and chemistries, and an increase in manufacturing volume



What goes up, must always come down

https://www.energy.gov/eere/vehicles...s%20per%20year.

 

Found this article from TechCrunch interesting - https://techcrunch.com/2023/07/11/so...-ev-batteries/

I didn't know about lithium dendrites before reading

As we shift away from gas- and diesel-powered engines and toward electrification, a recurring problem comes up: Batteries are heavy, and heavy is the enemy of efficiency. The quest for cheaper, lighter, more efficient, and safer batteries becomes increasingly necessary, and there’s a research rush happening right now.

You only have to look at the billions of dollars that car manufacturers — including Ford, Mercedes-Benz, Nissan and VW — have poured into battery-focused research and development to see the destination and the drive. In a nutshell: There’s a lot going on.

Movers and shakers on the battery circuit

The pursuit of better EV batteries has lasted for years, both inside the R&D labs at the automotive manufacturers and out in startup land.

Nissan has prototyped its own solid-state battery at its factory in Yokohama, Japan, which it hopes can go into production by 2028. Other car manufacturers have opted to put their funds into powering startups.

Factorial Energy, which emerged from stealth in April 2021, has an investment and partnership deal with Hyundai and Kia to co-develop and test battery tech in Hyundai EVs. However, it also has joint collaboration agreements with Mercedes-Benz, which was a “double-digit million-dollar investment” and an unspecified investment from Stellantis, which it hopes will see a rollout of solid-state technology in 2026. Based in Woburn, Massachusetts, Factorial has operations in South Korea and Japan and a subsidiary in Germany that was announced in March 2023.

VW has put $300 million into QuantumScape, beginning with $100 million in funding in 2018, followed by $200 million more in 2020. The plan was to have a production line for solid-state batteries established by 2025, again proving that it’s definitely not a quick road to success.

SES developed solid-state technology that works to eliminate graphite by painting the anode side of the battery with a proprietary substance. This coating allows the necessary accumulation of lithium without the buildup of potentially dangerous dendrites, which can puncture the separator and short circuit the whole system.
Solid Power is backed by BMW and Ford. Joint development agreements pointed to automotive-scale batteries coming off of Solid Power’s pilot production line to be delivered in early 2022, but that’s not yet happened. The company went public at the end of 2021 and SES went public in 2022. Both of them reported a loss shortly thereafter. The losses were not necessarily a shock, and they didn’t appear to spook either the markets or investors, but a loss is a loss. And it demonstrates just how volatile the battery manufacturing scene is.

Battery startups

The LG Energy Solution Battery Challenge offers a good look into the startup ecosystem. Its third iteration kicked off in October 2022, with 117 startups from 23 countries. All of the entrants were from different areas of battery development; 10 were selected as finalists, receiving prize money, the potential chance to collaborate with LGES, and possibly be considered for investment opportunities.

One of those 10 finalists was 18-person startup Natrion, founded by Alex Kosyakov and Thomas Rouffiac. Natrion was selected for its polymer-ceramic solid-state electrolyte material, called the lithium solid ionic composite, as well as the company’s demonstration of high-performance solid-state lithium-metal battery cells enabled by LISIC. If Natrion can scale up its production, which it believes it can, then it could bring about considerable changes to battery technology.

Natrion’s success in the LG Energy Solution Battery Challenge follows raising over $3 million in seed funding in venture capital money, in addition to about half a million in the Department of Defense grants and contracts. “We’re raising a Series A round that will be a priced round,” Kosyakov told TechCrunch+. “And that will be specifically to build our first production line for solid electrolyte material.”

Right now, the batteries that power electric vehicles are lithium-ion batteries that make use of liquid electrolytes. There’s a negative anode, which is usually graphite, separated from a positive cathode by a liquid electrolyte. The goal for battery manufacturers is to be able to swap the liquid electrolyte for a solid one, and in Natrion’s case, the graphite for lithium metal, but it isn’t a simple exchange.

“Lithium-ion batteries right now are all made with liquid electrolyte in the middle of the battery, through which charge moves,” Kosyakov said. “The liquid is very unstable against lithium metal, but it’s stable against graphite. And you have very fast degradation of the battery if you try to use liquid with lithium metal.”

Solid advantage

Near the top of the list for most applications is safety. By replacing the liquid electrolyte with a solid one, it reduces the prospect of dendrites — shards of lithium that resemble stalactites — growing on a battery’s electrodes. To prevent the dendrites from spreading from the positive to the negative electrodes, manufacturers usually include a separator between them. However, should the separator become damaged, the battery can short-circuit, which is what happened with the Chevy Bolt battery packs. Not exactly a win.

“We’re finding out a lot about EV safety right now,” Kosyakov said. “EVs are less prone to catching fire than ICE [internal combustion engine] vehicles from a probability standpoint, but the severity of a fire if you have one within an EV is much worse. And so how do we bring down that severity? Well, you can go to solid state, get rid of the liquid, and that solves that.”

But in addition to safety, solid-state batteries are also more efficient than liquid electrolyte lithium-ion batteries if you can switch the graphite to lithium metal. “But with lithium metal, you can store about 10 times more charge per pound than graphite,” he said. “So that’s what’s really exciting about lithium metal.”

This increase in energy density is especially valuable for EVs, because lithium metal battery cells have at least 50% more energy density than lithium ion. That means 50% longer driving range for the car.

Companies could use these more energy-dense batteries to overcome range anxiety or make smaller batteries. Smaller batteries might not get you as far, but they allow for an improved weight-to-range ratio in smaller vehicles that are less resource-intensive.

“If you can get more miles on a single charge, that means your battery has to do less charge discharge cycles over its life span,” Kosyakov said. “It’s better for the battery’s life and health. It’s also better for the consumer because with lithium metal you can also charge more quickly and with less hindrances…So we can have fast charging as well. So that’s what’s really exciting.”

When it comes to battery packs, liquid electrolyte batteries require cooling in a way that solid-state batteries don’t. By removing the cooling mechanisms, Natrion is trying to make solid-state batteries even more efficient and cheaper.

Scaling solid-state

“What our technology addresses is that nobody’s figured out how to produce lithium metal batteries at scale, and in a way that they’re stable,” Kosyakov said.

But by looking at existing battery factories that launched alongside the EV boom, Natrion thinks that adapting technology rather than starting from scratch will help it scale.

“What we found is a way to make solid-state batteries with [the] current process that exists with the current lithium-ion battery infrastructure, and then a way to get rid of other barriers and hindrances to commercial viability,” Kosyakov said. “For example, you’ll see solid-state batteries that need special conditions to work. Maybe they need the cell to be under pressure, to be clamped down. That’s really tough to achieve inside of an EV. Our batteries: They don’t need that kind of clamping, or they don’t need special temperatures to operate and that sort of thing.”

Lighter batteries help cars have much longer range, and safer batteries just make sense in the context of cars zooming along at motorway speeds. Whether the end goal is lighter cars that can deliver the same range with fewer battery cells, or cars that have longer range, it’s an all-around win for motorists. Manufacturers making batteries are all facing the same scalability issues, and for the average motorist, the tech can’t come along soon enough.

 

lots of investment, no guarantee of when. could be more than a decade, could be 2 years.

 

I have a battery thread, you should consider moving this post under that thread. I was actually going to write a post on battery degradation and talk a little bit about "dendrites", but have been really busy with work related stuff. As far as SSB's, I'll believe in them when I actually see one in action in an EV. I believe they will eventually happen, but at this point in time, concentrating on improving todays EV batteries energy density is more important

 

Already developed. It's just a matter of production cost that needs to be lowered to make it viable. I suspect it will be introduced on higher end luxury cars firs then trickle down.

 

No one ventures that far down in the forums Merged

 

What, no protest?