WetEV wrote:To get to higher horsepower, you need a larger battery, or a battery that can withstand a higher C rate. Or both.
The 2018 Leaf has more horsepower because of inverter and motor modifications, not because of the C rate of the pack. They did nothing to raise the HP of the 30kwh pack. Maybe there were marginal conditions in which the 24kwh pack would have gotten a bit of voltage sag with more power being drawn, but it's almost never the size of the pack that determines the power output of the motor in a non-race EV.
C rate of the 30 kWh Leaf pack is just about the same as with the 40kWh LEAF pack. Oddly enough, the 60kWh ePlus has almost the same C rate. As the pack gets larger, you can draw more power and maintain the same C rate. C rate limit is there to minimize localized internal heating. So maybe it isn't so odd.
Sure, you could increase the power of the motor and inverter without increasing the size of the pack. That would increase the C rate, which would do bad things to battery life. Just shorter battery life, if just a littler higher C rate. Loud, smelly, expensive and hot things if you push the battery pack too hard. Or unless you also change the cells to something closer to a PHEV cells that are designed to handle more power, which would increase cost and reduce range. Like in a race EV. Like the VW Pike Peaks car, with 48kWh of PHEV cells and 500kW of motor. That is a C rate slightly over 10. Chevy Volt cells are pushed to a C rate of 15 for drag racers. Don't do this for much more than a 1/4 mile. And don't try it with LEAF cells.
Want lower cost energy dense cells? Then the C rate limit is going to be lower. Using energy dense cells, the way to raise motor kW and keep the same cells and keep the same C rate is to increase battery kWh. Might raise battery size without a motor power increase, to get longer battery life at a lower C rate. Unlikely to accept less battery life just to get more motor power, unless you also shorten the battery capacity warranty.
The 24kWh LEAF pushed the batteries fairly hard. Do you think Nissan with the 30kWh pack should have:
A) Drop the C rate to improve battery lifetime (which they did)?
B) Increase the motor kW to make the car faster, and shorten the battery life?
Yes, the motor and inverter also have to change to get more power. Just keep telling everyone that. Maybe they will forget the battery issue.