I’m pretty aware that this is a “dumb” question, but my basic understanding of electricity can’t figure it out. I know the basic concept of resistance, currency and voltage, but I can’t comprehend how it takes so long to store charge in a battery
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Batteries are one of many ways of storing energy. They happen to be more efficient in specific use cases. Especially in compact, mobile applications.
For example, another method to store energy is to use electricity to pump water up a hill. When you want the energy back, you release the water and use it to spin a turbine. It takes time to pump the water the hill. If you try to pump the water too fast, the pipes will burst or you’ll burn out the pump, etc. It’s the same with the turbine.
Another method includes spinning a flywheel in a vacuum, which could twist into pieces if we attempted to accelerate or decelerate it too quickly. Etc. You cannot just give it maximum torque as the electric motor has thermal limits, the drive shaft could twist, the flywheel could exceed its maximum RPM, etc. You could also use an engine and transmission to spin up the flywheel, then use the transmission to link the flywheel’s output to a generator to convert that energy into electricity.
In the case of modern batteries, the way energy is stored is to use electricity to rearrange lithium ions in each cell. When you want the energy back, you reconfigure the connections to each cell, which begins the process of causing ions to migrate back to their original distributions. The side effect of this migration is electricity.
Just as it takes time to pump water or spin up a flywheel, It takes time for the ions to be optimally rearranged throughout each cell. And like spinning a turbine, charging or discharging a battery too quickly can cause it to catch on fire, etc.
Battery chemistry is a key factor in how quickly a battery can charge, in addition to the voltage of the system. The specific chemistry and internal structure of the battery determines how quickly the potential can be built up and released.
Capacitors can charge very quickly because they discharge very quickly. A more controlled, sustained discharge is required for electric cars, phones, etc. Some applications use capacitors to provide a boost to electric drivetrains, not unlike a shot of nitros oxide for an internal combustion engine.
IOW, storing energy in a battery uses electricity to build a chemical potential, which can be converted back into electricity again. Building and releasing that potential isn’t instantaneous.
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