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Batteries or accumulators are real energy recipients, in fact they are used to accumulate energy with the intent of using it in times of need.
Batteries are used in photovoltaic systems (but not only) to supply energy when the system does not generate it (in the evening or on bad weather days).
There are different types of batteries, the oldest and most well-known lead-acid battery, still used on a large scale, and the most modern and innovative lithium or super capacitor batteries.
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