Re:How Lotus is going to build lightweight electric sports cars
by nabilhat on Saturday September 25, 2021 @03:00PM
(#28655373)
If 28 kWh is enough for an entire Formula E race, I think 33.2 kWh in a Lotus would work out okay.
Re:How Lotus is going to build lightweight electric sports cars
by ggreer on Saturday September 25, 2021 @04:04PM
(#28655827)
28kWh isn’t enough for a Formula E race. They swapped cars in the middle of the race back when they used those smaller batteries. They now use 54 kWh batteries[1], though power output is limited to less than a Tesla Model 3.
Next year they’re supposed to increase power output to 350kW, which is comparable to a Model 3 Performance. Of course Formula E cars are much lighter, so acceleration and handling are far better than the Tesla sedan.
Re:How Lotus is going to build lightweight electric sports cars
by ghostpepper on Saturday September 25, 2021 @06:37PM
(#28656768)
Why can't you brake aggressively with regenerative braking?
Re:How Lotus is going to build lightweight electric sports cars
by zrm on Saturday September 25, 2021 @07:55PM
(#28657169)
Cars can typically stop quite a bit faster than they can accelerate. This is especially true for two wheel drive cars because two wheel drive cars still have four wheel brakes.
To brake as fast as the traction limit on the tires, which is what you get from disc brakes, you would need four wheel drive and then bigger than normal electric motors and everything else to be able to absorb that much power that fast.
And then the battery would get really hot, especially if it was small.
In normal driving you accelerate to highway speeds and then coast, or you're in city traffic and benefit from regenerative braking.
On a track, you brake late on purpose because it's faster, but to stop that fast you have to rely more on traditional braking and can't recover the energy. Then you immediately want to accelerate back to high speeds again.
If you put a small battery in an electric track car, it would be flat in ten minutes.