What’s the Truth?
Most production EV batteries are warrantied between 7-10 years and from 70,000 to 100,000 miles. For example:
| Manufacturer | Warranty Given | Source |
| Tesla | Minimum 8 years, 100,000 Miles | |
| Nissan | 8 years, 100,000 miles | |
| MG | 8 Years, 100,000 miles | |
| VW | 8 Years, 100,000 miles | |
| BMW | 8 Years. 100,000 miles |
The warranty limits are based on the energy it will carry when it was new and fully charged. This is generally 70-80% capacity They will work after the warranty period (just like an ICE engine).
As a side note, the above manufacturers that offer a engine warranty tends to only offer a 3 year 60,000 mile on the engine.
Fact is that a manufacturer will not offer a warranty (on any item, let alone a car), if they can be assured that the vast majority of cars will not have issues. This is extremely important.
What’s 100,000 miles?
According to a MOT study, the average mileage of a UK motorist is around 7400 miles . Therefore:
- These batteries will do 56,000 miles on average before the time on the warranty ends
- Or alternatively need to cover 12,500 miles a year to achieve the 100,000 miles. For most people, this is unlikely, although not impossible.
What about after 100,000 miles?
Regarding data, there are not many peer-reviewed studies I can find on this.
There are multiple data entries from different sources which identify that most batteries will maintain at worst 80% health for at least 5 years In fact, after 9 years, according to this study, on average the battery is fully working and at 85% degradation .
In general, battery replacements are not as popular as once imagined. In fact Nissan believe that the vast majority of batteries placed into cars are still inside cars
Tesla (and many other manufacturers with active battery management), are likely to fare significantly better . The vast majority of manufacturers (with the exception of Nissan with only their LEAF), have thermal battery management.
This is different to ICE vehicles. Although they both do decrease in performance over time , unlike a petrol and diesel engine, this is a permanent degradation. It cannot get better without a change of the cells in the battery pack.
What Can Be Done?
There are methods to bring back the battery health which do not involve replacing the entire pack, including replacing individual cells , which will be significantly cheaper.
In the case of this video, this Nissan Leaf had reached 120,000 miles and was abused with multiple rapid charges per day.
In the unlikely event the capacity drops below the minimum warrantied capacity, the pack will be refurbished (to get back up to 70-80%) or replaced.
However, if a full replacement is required, they will repurpose the battery for some other use (battery storage for solar/wind etc1), or recycle. This has the added benefit of having value when removed and replace.
What about out of the 100,000 mile warranty?
There have been some cases where it has been called out as prohibitively expensive, and you would be right, if you went straight to a main dealer.
This is the equivalent of going to a main dealer for an out-of-warranty engine replacement (in this case, £9000, £12000 and £6500!)
Just like with a refurbished engine replacement (much cheaper), refurbished batteries do exist, and EV breaker yards , alongside independent EV garages are popping up to supply, but also fitting reconditioned or salvage packs
One huge advantage of this, is that a battery upgrade can also give another advantage of improving the original range of the vehicle, especially if larger batteries were made for that platform.
For example, there have been Nissan LEAFs that have gone from an original 24kWh to 62kWh. This is not inexpensive at the moment (24kWh to 62kWh is around £12,500 including fitting) .
This is definitely not cost effective given that a Leaf can be had for less than £4000. However, your Leaf will be in effect upgraded from a reasonable 80 miles to over 250 miles in a couple hours. This can even be a DIY repair, if you are in that mindset (and does not require a vehicle ramp).
In the case of Dala’s EV Repair 3NFG}”], DIY was £1800 equivalent, with a 24kWh to 30kWh replacement. This did involve selling the original battery pack as a DIY stationary storage device.
Final Thoughts
In conclusion, EV batteries are certainly lasting longer than 3 years, are warrantied to 8 years and 100,000 miles. When buying a 3-4 year old EV (which is more likely than new), there is not much to worry about.
Finally, when you inevitably need a replacement (once your vehicle has gone beyond 100,000 miles or beyond 13-14 years of average usage), although the equivalent of a new engine replacement in price, replacement is certainly possible.
The main issue with this information is that battery pricing is coming down by leaps and bounds – it is and will likely be impossible and unrepresentative to determine the cost of a battery in a EV bought in 2024 by the time the battery actually warrants a replacement, using current pricing.
FYI: If you want some anecdotal evidence on this, my car has reached 60,000 miles2 as of this update, and is at 86% SOH, and still kicking!
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