New EV worries

[AKrietzer]

As a new - first time -;(not yet- ) EV owner what do I need to know about batteries?
I am currently having to replace a 4 or so year old battery in a 2011 Hyundai Sonata, on it:s second battery, less than 4 years on this battery. My 2012 Tundra is on battery #2, my 2003 Tundra lasted over 10 years. How long should I expect my main (not 12 volt) batteries to last? I know EVs generally have an 80,000 mile warranty.

 

[Chapman]

Your battery should last 10 years and 200,000 miles. You may or may not still be under warranty by the time it happens. Regardless, you may be able to replace/repair some of the cells instead of the whole battery to get many more years out of it. Also, battery technology is getting better every year, so you may be able to get a much better battery (higher range and lower weight) by the time your battery goes. The costs for the battery itself should be quite a bit lower as battery technology matures and they are manufactured in larger volumes. Plus, more shops will be able to do the work and they will be more familiar with it, reducing the labor time needed to make the swap. I wouldn't worry about the battery at all - especially since it's from a reputable supplier, SK On, who also does the batteries for Ford).

 

[AZFox]

The federally mandated minimum warranty is eight years or 100,000 miles.

There are a lot of factors that influence long-term battery health. Put another way, you can make your battery last by using it properly and you can degrade your battery by using it improperly.

There are tons of articles on this topic. Here's one that seems pretty comprehensive:
Battery Car Lifespan: How Long EV Batteries Really Last in 2025

 

[The Weatherman]

The latest evaluations being published by the HVB industry indicates the original estimates of battery longevity may have been woefully short. There are some estimates out there that FLP’s will retain their 80% capacity for more than 10yrs and 500,000 miles.

Some of the earliest Tesla cars are still on the road and going strong.

 

[ScooterAsheville]

They essentially outlast your ownership of the vehicle, and the next buyer's ownership of the vehicle, and the owner after that. I see some links were given above. There is a company call Recurrent that is valuable if you're buying a used BEV (link at bottom). They can assess battery health in many cases.

Also, BEV batteries come with manufacturer warranties - typically 80% at 8 to 10 years, though that varies. But be aware that OEM warranties typically don't cover road hazard claims - just as an OEM would not cover your car running over junk on the raod that trashes your underbody. BEVs are unique in that the most expensive part in the car is at the bottom - protected but still exposed to potential damage.

As with all things automotive, there are some horror stories out there. Sometimes a small dent in a battery enclosure will result in the OEM declaring the battery totalled from road damage - and in this case you have an insurance (not warranty) claim for as much as $20,000. Go to the Motormouth site for a famous horror stary from Canada. The moral there is to make sure your insurance policy covers road damage to an expensive BEV battery - as that will typically not be part of your manufacturer warranty Not trying to scare anyone with this, just a rare case to be aware of. The moral is to know your insurance coverages.

There are things about which you should educate yourself when it comes to your battery system. Charging profiles and speed. Performance in cold weather, if applicable. Phantom drain when parked. Recommended charging percentage (if NMC, typically 80%. If LFP, typically 100%). The construction of the pack enclosure itself - is it repairable or not (example, Tesla is not). Sorry, but in 2025 you do still need to understand BEV battery systems in order to make a wise buying decision. People who tell you that's not true are being more than a little bit disingenuous.

https://www.recurrentauto.com/

 

[Dorbiman]

Realistically, the lifetime of the vehicle. Battery degradation tends to decrease over time, so as traction batteries age, they degrade less and less.

Really though, there's nothing special you need to do outside of charging. Traction batteries are designed to function in extreme cold; you can read about VW's testing HERE.

As far as charging goes, batteries don't like to sit for periods of time at 0% or 100%. People use 20-80% as a rule of thumb for NMC batteries (like the Slate Truck has), but Volvo & Polestar recommend capping charging at 90% for their NMC batteries.

NMC batteries are typically rated up to 1500 charge cycles, meaning 1500 cycles of 0% to 100%. If you plug in at 55% and unplug at 80%, that's only 1/4 of a cycle. What this means is that the battery is expected to maintain ≥80% of it's capacity (State of Health) up to that 1500th cycle. So even at that point, you've gotten perhaps 375,000 miles out of a battery (assuming a relatively standard 250 mile range, perhaps less for the Slate Truck) before your battery is at 80% State of Health.

Recent studies show that modern batteries are actually outperforming the lab predictions, by 30-40%. You can read about that HERE. Lab testing is harsher on batteries than real world use cases, so you can realistically expect a modern NMC battery to last a very, VERY long time.

 

[Paul]

As a new - first time -;(not yet- ) EV owner what do I need to know about batteries?
I am currently having to replace a 4 or so year old battery in a 2011 Hyundai Sonata, on it:s second battery, less than 4 years on this battery. My 2012 Tundra is on battery #2, my 2003 Tundra lasted over 10 years. How long should I expect my main (not 12 volt) batteries to last? I know EVs generally have an 80,000 mile warranty.

Another thing to consider is that ICE engines and transmissions aren't without failure out of warranty. And the price of a blown engine or a transmission is probably getting pretty close to battery replacement. In most cases the battery warranty is longer than the ICE warranties that are usually 6/60. The transmission on the EV is a much simpler affair. So in the end anything is a risk that it could cost you some money out of warrant.

 

[SparkYellow]

Appreciate the info!

Also a soon to be first time EV owner here. Before I found out about Slate, I considered getting a used Model S with lifetime free supercharging. There are always a few of them on FB marketplace. But I didn't know enough to assess used battery condition/life to make that jump. The premium sedan body style also doesn't fit me.

I agree, typical car batteries don't seem to last very long, especially the mid-range priced flooded units from auto part stores. Earlier this year I replaced the battery from my CX-3 because it was leaking after only two years. Last week I replaced the battery in my Suburban with an agm unit and will see how long it lasts. I haven't yet paid for premium batteries like Optima, but I have read great things about them.

 

[Pir8Neverlies]

As a new - first time -;(not yet- ) EV owner what do I need to know about batteries?
I am currently having to replace a 4 or so year old battery in a 2011 Hyundai Sonata, on it:s second battery, less than 4 years on this battery. My 2012 Tundra is on battery #2, my 2003 Tundra lasted over 10 years. How long should I expect my main (not 12 volt) batteries to last? I know EVs generally have an 80,000 mile warranty.

A 12 v battery lasts about 4 years. You really shouldn’t have to worry about you high voltage battery most are warrantied from 80-100k