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Its a funny situation: they a put larger battery in the car, which makes the car heavier. Then they derate the battery to give you less mileage with the added “benefit” that you carry with you a deadweight that you can’t get rid of and contributes further to reduced mileage.

And someone at VW looked at this and said: amazing idea.

My single take from this is that batteries have become so cheap that you can put more in a car and still make a good profit.

It would have been nice if the savings would be passed on to the consumer.



I'm confused, what do you mean by "derate the battery", and how would that cause some of the battery to be deadweight?

It sounds to me like they're just limiting the kW output of the pack.


> It sounds to me like they're just limiting the kW output of the pack.

That's what he means by derating. Using the battery as if it were specced lower than it is. The deadweight is that you're hauling around a battery that is heavier than it needs to be if it were actually that spec.


I mean you have a 100kW battery that is limited by the software at 70-80kW. This is what I mean by de-rating.

Secondly, a 100kW battery is heavier than a 70-80kW one.

If you don’t pony up for the upgrade fee, you carry around all the time probably 50kgs of useless mass. More mass, less mileage.


There's no additional battery cells, is the 50kg extra cooling or something?


OK, let’s try this another way: they could have sold a car with a say 70kW battery. Instead they are selling it with say 100kW battery.

Am smaller battery would weigh less than a bigger battery.

Because they de-rate the battery via software, you are carrying a bigger battery which weighs more than a smaller battery, while you only get the mileage of a smaller battery.

Hence, you have deadweight in your car.


Oh man all this theorizing and getting units of measurement wrong.


It is not dead weight. De-rating is good for longevity.


This. Overclocking has increased probability of earlier failure but within warranty period. You are essentially paying for this.

Giving people options how to pay for this is not a bad thing, as long as you can pay outright, per month, per mile, per unit delivered.


Any car with LiFePO4 batteries has a battery pack which should outlast the rest of the car.

300 miles per charge, 5000 charges, that's 1.5 million miles.




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