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Comment by dogma1138 | Hacker News Reader

No it doesn't it's the complete opposite the battery capacity decreases with the max current draw from each cell...

If you have a battery with high capacity it would have a very small sustained draw and vise versa.

The chemistry that allows for dense storage doesn't allow for high capacity and vise versa.

Some of the new chems that are specially designed for EV's try to marry the best of both worlds but in both cases you can have a considerably higher capacity or considerably more power if you use chem that was optimised for either.

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Yes, changing chemistries does change the energy/power density ratio. However I was referring to within a single chemistry. Hence why the higher capacity Teslas have higher performance too.

An ICE doesn't get faster if you put a bigger fuel tank in.

Not really if you just increase the capacity of each cell you decrease the maximum power draw so the performance goes down.

If you just add cells you increase the weight of the car which can also have a negative or neutral effect on performance.

This doesn't make sense. By that logic, a lithium battery the size of a house wouldn't be able to power an LED.

If you have two lithium batteries which are identical with the exception that one is double the capacity, the larger battery will be able to provide double the current at the same voltage and thus double the power. Lithium batteries are rated for current draw as a multiple of their capacity.

It's nothing to do with the size of the battery it's with the chemistry and yes a batter the size of a house might very well not be able to power a single LED because of its internal resistence.

Lithium batteries are rated for current draw based on their chemistry please do some basic reasearch.

And no if you have 2 identical 18650 they'll have the same density and sustained and peak current draw if not they are not identical.

Cell size, chemistry, internal resistance, breakage and short currents etc are all variables based on the exact make of the battery.

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