Extra modules would allow you to lower per cell charged voltage while keeping the capacity. That would extend the life of the entire pack.longevity
Extra modules would allow you to lower per cell charged voltage while keeping the capacity. That would extend the life of the entire pack.longevity
What are you using for your motor/inverter? What vehicle?I'm in the early stages of building an EV and about to buy the battery.
I have a 150kw capable motor/inverter, and main priority is acceleration performance over range.
I'm looking at using Leaf Gen4 modules.
I could buy 24 Gen 4 modules to make a standard 40kwH Leaf pack
That's two sets of 96 series Cells in parallel at 350v
My budget could stretch to 28 Gen 4 modules to make a 46kwH pack
two sets of 112 cells in series at 408v.
As mentioned, I'm not so bothered about range (expect to recharge every night) so the extra 6kWh is not important, but my thoughts were that by having a higher pack voltage I can extract more power at a safe current for the battery.
My question to those with more experience than me is:
Is it worth spending extra money and carrying the extra weight of 4 additional modules for the benefit it will give me? Considering that acceleration, longevity and cost are important to my project.
Thanks
Dan
Based purely on the mass I have for Leaf 24kwh and gen4 40kwh cells yes. Tesla modules are irrelevant to the comparison. I have leaf modules available to meAre you sure about that added weight? 18kWh of Tesla modules is about 75kg. Seems like you're off by a factor of 2 (2.2?).
Well, to your original question, Power = Voltage x Current. Voltage is free, Current requires copper and cooling. We significantly over coppered and require cooling only at highway speeds in 85+F°. Going with higher voltage is much easier. I will say, we are currently stuck as we lost two modules from our pack (0 Volts!) the other Gen 2 modules are still testing out at ~90% SOH. We are not finding any aftermarket modules above 70% and new is $400.ea! By extra and put a few aside.