Hi all,
A question to which the obvious answer is no, because of safety. However, I am still looking into it.
Knowing that I have experience with specifically these BMW i3 NMC chemistry batteries (I have already been using them).
Knowing that NMC chemistry can have thermal runaway (above 70 degrees Celcius).
Would it be worth a shot to buy a battery from a BMW i3 that had its rear burned out?
I would do some proper stresstesting on the modules, and I would only use them at less than 0.1C charge and discharge. And I wouldn't use the electronics in the front.
If I were to buy the battery, I would place it on a concrete slab at a safe distance from my house. With some water next to it.
Even the wind direction is almost always away form the house and I have rainwater storage.
But of course, you should just buy some new batteries or at least a used battery from an EV that didn't catch fire.
However, the predictable thing is that this one is much cheaper and think I might haggle it down further because of the shitty proposition.
To my idea they can have never been that hot, because otherwise they would have gone into thermal runaway and have the whole pack and car burned down.
But then again, to my opinion, you could never really trust these modules.
See the damage. There is a molten connector, and some minor smoke/heat damage on the pack. But even a sticker is still readable.
So the questions is, what heat did it see, and did it actually heat up this whole pack which is quite some mass.
Even if I don't do it, this is a fun discussion imho. Would you run away from it?
Or would you buy it, lets say at 20% of market price, knowing that you can use it in a relatively safe manner? (meaning that a fire wouldn't take other things with it)
What worries me the most is the bubbles on the top of battery cover. It looks like some heat went on the top of the battery as well.
And I think it must have been more than 60 degrees Celcius to cause that kind of damage.
For those who don't know, this is a 44kWh pack using NMC chemistry.
A question to which the obvious answer is no, because of safety. However, I am still looking into it.
Knowing that I have experience with specifically these BMW i3 NMC chemistry batteries (I have already been using them).
Knowing that NMC chemistry can have thermal runaway (above 70 degrees Celcius).
Would it be worth a shot to buy a battery from a BMW i3 that had its rear burned out?
I would do some proper stresstesting on the modules, and I would only use them at less than 0.1C charge and discharge. And I wouldn't use the electronics in the front.
If I were to buy the battery, I would place it on a concrete slab at a safe distance from my house. With some water next to it.
Even the wind direction is almost always away form the house and I have rainwater storage.
But of course, you should just buy some new batteries or at least a used battery from an EV that didn't catch fire.
However, the predictable thing is that this one is much cheaper and think I might haggle it down further because of the shitty proposition.
To my idea they can have never been that hot, because otherwise they would have gone into thermal runaway and have the whole pack and car burned down.
But then again, to my opinion, you could never really trust these modules.
See the damage. There is a molten connector, and some minor smoke/heat damage on the pack. But even a sticker is still readable.
So the questions is, what heat did it see, and did it actually heat up this whole pack which is quite some mass.
Even if I don't do it, this is a fun discussion imho. Would you run away from it?
Or would you buy it, lets say at 20% of market price, knowing that you can use it in a relatively safe manner? (meaning that a fire wouldn't take other things with it)
What worries me the most is the bubbles on the top of battery cover. It looks like some heat went on the top of the battery as well.
And I think it must have been more than 60 degrees Celcius to cause that kind of damage.
For those who don't know, this is a 44kWh pack using NMC chemistry.
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