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Discussion Starter · #1 ·
I noticed there is a seller on ebay with something like 20+ complete BMW i3 battery packs, 22 kWh, circa 2014-2017. Has anyone tried to use cells from the i3? If I remember right, in the i3 they are liquid cooled. I don't think I could pull off liquid cooling of batteries in my conversion project. If anyone has tried using them, I would really like to hear what your experience has been. Thanks
 

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I will be using them but I won't be using liquid cooling, my Mini will be an occasional car without DC charging though.
I would say have a good look at where you can put them as they are quite bulky, approx 310x410x150mm


Sent from my moto g(8) power lite using Tapatalk
 

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I will be using them but I won't be using liquid cooling, my Mini will be an occasional car without DC charging though.
I would say have a good look at where you can put them as they are quite bulky, approx 310x410x150mm


Sent from my moto g(8) power lite using Tapatalk
I am using 2 modules in a sidecar motorcycle. 48v x 2 =96 volts no bms (I am a believer in bms) and no cooling.
I have not noted any elevated temperatures at all. I believe the newer higher amp modules the 90ah and 120ah versions need more aggressive cooling.
 

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Discussion Starter · #4 ·
I will be using them but I won't be using liquid cooling, my Mini will be an occasional car without DC charging though.
I would say have a good look at where you can put them as they are quite bulky, approx 310x410x150mm


Sent from my moto g(8) power lite using Tapatalk
I've pretty much decided to go with used Tesla Model S batteries. I won't ever require fast charging or ever expect "insane" mode driving.
 

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Discussion Starter · #6 ·
I spoke with EV West. Their opinion was, that in my application, liquid cooling would not be necessary. Do you have direct experience with Tesla S batteries powering a '96 Miata or other 2000 Lb vehicle using a Netgain Hyper9 96V drive system? EV West sells this kit for VW bug and Ghia, all air cooled batteries. I guess they would have many unhappy customers if this configuration overheated the batteries. So, as you say, "my wallet" but EV west provides a one year guarantee on the batteries.
 

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My builds will have batteries that last at least ten years. Like heck I'm going to abuse them for a year and toss them after shelling out $16 grand. The cost of a pump and radiator is three hundred bucks, assuming a benign climate.

The wider the temperature swing of the cells, the shorter the life. Tesla Model S from 2012 are still on the road with minimal degradation.

Like I said, it's your wallet. EV West build customers have bags o money, many of the cars are for show and Sunday drivers, and the operating environment for most of their builds is in SoCal. Pretty steady year round temperatures.

One year on a battery is a build, not design, defect warranty. Do what you want, but if you're chucking batteries often, seems penny foolish to do so with an expensive one. You can even arc weld with uncooled Tesla modules if you want.

A 96V system will run high current all the time, unlike a 400V one. You're running 500A down the highway while the 400V people are running 125A.

2C continuous discharge rate air cooled vs 0.5C continuous liquid cooled. No brainer which battery will get toasted first.
 

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Discussion Starter · #8 ·
Well, Remy, all I can say is I'll have to monitor the battery temperatures carefully, and if liquid cooling is required, then it's a modification I'll have to make. I only intend to have a 20 to 25 KWh battery, split into 3 locations, maybe forced air cooling will be enough. You do tend to exaggerate. 500A and 96 volt is 48 kW. Only gonna happen on the occasional hill at 60 MPH.
 
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