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Discussion Starter · #1 ·
Sorry this is not strictly about Volt/Ampera....

Imagine a fictional EV, one without a battery or cabin heater

If an EV is driven from 100% to 10% and it travels 150 miles during weather of 6c, then recharged to 100%

The same EV is driven from 100% to 10% and it travels 220 miles during weather of 20c

Do both EV’s use the same amount of energy ? does it cost the same to charge both EV’s back to 100% ?
 

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Assume the route / speed / wind are all the same and only the temperature is different I would expect the warmer temperature to use less energy due to the air resistance being less, warm air is thinner ;) This can be seen in the Ampera as longer range on warm still days.
Batteries themselves are effected by temperature as well and do not hold charge as well when cold - higher internal resistance at low temperatures leads to more losses. See Battery University
Some EV's warm the battery, some even have a "winter" version sold in nordic countries to cope with low temperatures, I believe the Leaf has a battery heater in Norway for example.
 

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Discussion Starter · #4 ·
Thanks for the detailed reply, it doesn’t answer the question as to wether in both instances the same actual amount of energy is used. I guess I could experiment. Keen to know :

1, is less energy available, thus a shorter range is possible

or

2,the same amount of actual kWh is consumed, however somehow it’s wasted within the battery due to the slowed or hindered chemical reaction ?
 

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Thanks for the detailed reply, it doesn’t answer the question as to wether in both instances the same actual amount of energy is used. I guess I could experiment. Keen to know :

1, is less energy available, thus a shorter range is possible

or

2,the same amount of actual kWh is consumed, however somehow it’s wasted within the battery due to the slowed or hindered chemical reaction ?
I’d say it’s both.

In scenario 1, there is less energy in the battery to begin with due to temps, and the other factors you mention mean there are more losses as that energy is translated into distance achieved.

For 2, there is more energy available, and the factors mentioned mean that there are fewer losses that translates to more distance achieved.

As for the battery charging part of the question, you can only replace what has been used, but charging losses will again vary by temp.
 
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