Once the original chemicals are all used up, the battery is dead. If you could reverse the reaction or add more of the ... When electricity is flowing, the cathode gains the same number of electrons ...

All these benefits come at a cost ... That's because, like other types of batteries, battery backups lose storage capacity over time. To account for this, battery backups include a warranty ...

Our top pick for the best home battery and backup system is the Tesla ... so we've included a variety of picks to fit all types of needs and budgets.