Speak EV - Electric Car Forums banner

1 - 14 of 14 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
I can't find any details on the shelf life of the batteries on the i8.
I believe the cars currently have an 8 year warranty on the batteries in that if they drop below 70%, they are replaced FOC.
Questions:
1. When the time comes when the owner notices a deterioration in overall battery efficiency, will/can battery modules be replaced once identifed - individually or must the entire pack be replaced as one?
2. How much would an entire battery pack cost (presumably from the main dealers)?
3. How easy is it to replace modules or the entire pack?
4. Has anyone had any dealings with this subject to date?

Presumably a BMW i8 sold second hand without a battery warranty - is next to worthless?

Thanks in advance
 

·
Moderator
Joined
·
9,719 Posts
Battery is likely to last 15yrs plus before warranty levels would kick in. Battery modules cost 800 Euros, there are 3 units to make a full pack and can be replaced individually. Full pack replacement is less than half a day labour.

I am not aware of anybody needing a warranty replacement.

Presumably a BMW i8 sold second hand without a battery warranty - is next to worthless?
Its worth as much as somebody is prepared to pay for it.
 

·
Registered
Joined
·
2,587 Posts
You can’t find any information about the battery longevity because it isn’t really an issue and besides the cars haven’t been out for 8 years yet so it’s highly unlikely anyone has had to have a degradation related replacement under warranty or otherwise.

Batteries aren’t useless once they reach 70% either.
So, out of warranty, as long as you still get the range you need out of the batteries then there’s no point replacing them.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #4
Jack, thank you. I assume you are talking about the BMW i8 battery pack and not relating to your knowledge of Tesla batteries and their longevity.
Do Tesla and BMW use the same supplier/technology?
AttheVan - reading american forums about the i8, battery life is very much an item because the first i8's have now been running around for nearly 5 years and their warranties will only have another 3 to go.

What are long term EV owners saying about their battery life, replacements and costs?
 

·
Registered
Joined
·
2,587 Posts
Well there are taxi firms who do multiple rapid charges a day and have batteries that are still showing all bars after 150,000 miles. Teslas are around that have done 400,000 hard miles with some degradation but nothing like the catastrophic stuff that was predicted and all the news outlets try to make out.

Then there are the poor Leaf owners in places like Texas where their uncooled batteries had to be replaced due to excessive heat related degradation within the warranty period and who are still suffering.

So, it all depends if you keep cars beyond their warranty periods, if you do then you’ll probably only have slow degradation in most European countries, especially if the battery is cooled/heated.
If you do have to replace the whole battery out of warranty then for things like the Nissan Leaf there are estimates of £3000 to £4000 to swap the entire battery.
 

·
Registered
Joined
·
502 Posts
There’s a YouTube video of someone stripping down and replacing the cells in a Prius battery for a very reasonable cost. The battery packs in the small range PHEVs like the 225 330, and the i8 can’t be much bigger. I would hope when and if out of warranty battery packs start to fail, a replacement industry might grow up, offering swappable reconditioned packs.
 

·
Registered
Joined
·
626 Posts
Battery is likely to last 15yrs plus before warranty levels would kick in. Battery modules cost 800 Euros, there are 3 units to make a full pack and can be replaced individually. Full pack replacement is less than half a day labour.

I am not aware of anybody needing a warranty replacement.



Its worth as much as somebody is prepared to pay for it.
BMW i8 has 7.1kwh battery

Are you saying that 3 modules will make the full 7.1kwh battery ... 2.4kwh at 800 euros ... is around 333 euro per kwh, which is a very good price ... almost too good.

I know Mitsubishi was asking over 8000 euros for the 12kwh battery of the Outlander .. so with a asking price over 670 euro per kwh

Another battery price is 9.5k Euro for 35kwh from Sono Sion .. which make 270 Euro per kwh .. but this is part of the car sales process, so 333 euro per kwh in replacement is a super price
 

·
Moderator
Joined
·
9,719 Posts
Are you saying that 3 modules will make the full 7.1kwh battery ... 2.4kwh at 800 euros ... is around 333 euro per kwh, which is a very good price ... almost too good.
I correctly designed system that can be supplied as small modules and easily serviceable = lower cost. Mitsu have to provide the entire batter they can't easily swap a module unless they break a full unit.

BMW will only sell batteries to authorised persons with battery test equipment and certification, the defective module is returned to BMW for test and recycling - might even find its way into the Leipzig grid storage battery complex.

Its yet to be seen if Sono can produce anything, the "prototype" is a rework of an i3...
 

·
Registered
Joined
·
626 Posts
I correctly designed system that can be supplied as small modules and easily serviceable = lower cost. Mitsu have to provide the entire batter they can't easily swap a module unless they break a full unit.

BMW will only sell batteries to authorised persons with battery test equipment and certification, the defective module is returned to BMW for test and recycling - might even find its way into the Leipzig grid storage battery complex.

Its yet to be seen if Sono can produce anything, the "prototype" is a rework of an i3...
Are you saying that the i8 battery pack is your design ?

:eek:

PS: The Mitsubishi big battery should not a real issue ... if they recycle/ re-purpose properly ... the cost of swapping should be the same as per the BMW replacement.

PPS: The BMW 333 Euro per kwh ... it still sounds almost too good to be true

PPPS: The big battery from Mitsubishi it is internally more modular then the Tesla battery packs ... each single cell can be easily replaced ... there is even a private person whom replaced the internal battery cells with higher capacity cell from china ...
 

·
Registered
Joined
·
45 Posts
Just watch the fine print on battery warranties. I think the BMW 8 year battery warranty only applies to the first owner. 2nd owner only has the normal car (2 years?) warranty.

Either way it's a non issue for most people as pointed out above. Battery degradation is a much less common problem than say timing belt/chain or diesel pump failure on IC engine
 
1 - 14 of 14 Posts
Top