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DoomGoober t1_j23sdmh wrote

Reply to comment by Commercial-Army2431 in ELI5 why do electric vehicles have one big battery that's hard to replace once it's expired, rather than lots of smaller ones that could be swapped out based on need (to trade off range/power/weight)? by ginonofalg

As I understand it, car batteries are arranged in packs of serial or parallel configurations to intentionally harness the resistance of serial or parallel to achieve desired voltage.

Thus using multiple batteries (and the resistance introduced by serialization or parallelization) gives the designer some control over the voltage.

Whether this is a side effect of needing multiple batteries for other reasons or a specific desired feature, I don't know, but it reduces the need for resistors.

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VrebPasser t1_j24m8z3 wrote

Not quite true as you put it, but the general principle applies. It's about voltage stacking and the same current being drawn from multiple sources.

Think of it as a slide going from the top of a building to the road below. You have a number of people that want to slide down (that would be the load). If you have one huge slide, the people will be hurting each other as they descend. Therefore, you add more paralel slides (batteries) so they can redistribute themselves and be less cramped (less overloaded system). By adding more batteries in series, you make the slope more steep so the people get down faster (more force to "push" them).

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