100V lithium ion battery - Vextrek

[Vextrek]

This is our new 100 Volt lithium ion battery pack for the next electric go kart project. The two modules shown below will be connected in series to obtain a nominal voltage of 100V and the pack has 46 aHrs of energy storage capacity. The soft drink was included for relative size comparisons. We connected the lithium cells with .25mm thick pure copper using a professional-grade pulse arc welder. We are also using a “Dilithium” Battery Management System to properly balance the pack. The pack utilizes 10 thermistors attached all around both modules to constantly monitor cell temperatures.

 

[DonCox]

This is our new 100 Volt lithium ion battery pack for the next electric go kart project. The two modules shown below will be connected in series to obtain a nominal voltage of 100V and the pack has 46 aHrs of energy storage capacity. The soft drink was included for relative size comparisons. We connected the lithium cells with .25mm thick pure copper using a professional-grade pulse arc welder. We are also using a “Dilithium” Battery Management System to properly balance the pack. The pack utilizes 10 thermistors attached all around both modules to constantly monitor cell temperatures.

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How hot do your batteries get, can you monitor each individual sensors? I use the same cells, but in a none max current application. Mine are 20S8P for a maximum of 360A, but the motor/ controller can only draw 200A, so I don't expect a lot of heat, but I was wondering , do you see any heat problems, or what do you see?
Thanks

 

[Vextrek]

How hot do your batteries get, can you monitor each individual sensors? I use the same cells, but in a none max current application. Mine are 20S8P for a maximum of 360A, but the motor/ controller can only draw 200A, so I don't expect a lot of heat, but I was wondering , do you see any heat problems, or what do you see?
Thanks

No heat issues with the previous pack (20S/21P) but that was using Samsung 25 cells and pulling 500A max. Plan to test this new pack extensively on a go kart in early March and will report the results. Each of the modules have 5 separate thermistors placed around the pack and the SOC gauge we use allows us to see which (if any) thermistors indicate a problem.

 

[Vextrek]

About to track test this new battery. Have 10 thermistors (5 on each module) so will be monitoring heat closely. Will report back.

 

[Vextrek]

Update:110 mph in the 1/4 mile and 87 mph in the 1/8 mile. Still working on ways to improve the 60ft times but we are pleased with the results. The Vextrek lithium battery performed well and all other drivetrain “vital signs” were good. Made about nine passes at the Carolina Dragstrip in the 90+ degree heat.

 

[Vextrek]

Back-to-Back 1/4 mile passes at the Carolina Dragway. Tentative plan is to be at the Lamar County Speedway on June 11 and the Atlanta Motorsports Park in late June or early July. Target Performance Level: TAG Senior Series

 

[Vextrek]

Close up shot of the spot welds using .25mm thick pure copper on the Molicel P26A cells. We have a pulse arc welder which allows us to weld copper consistency.