Solar batteries that can be used for off-grid zones need to be reliable and tough. Deep-cycle batteries are crucial because they can be repeatedly discharged and recharged. Lithium-ion deep-cycle batteries have high energy density, a long cycle life, and require little maintenance. Smaller off-grid layouts can use lead-acid batteries, which are cheaper. To ensure non-stop power supply in off-grid areas, the battery size must be carefully estimated with daily energy consumption, number of cloudy days to be covered, and available solar panels in mind.