Battery Lifetime, Efficiency and Care

The battery bank should be installed, preferably on its own, in a weather & frost protected, well ventilated shed or other enclosed area. Ideal temperature is ~ 20 ºC and should not be more than 43 ºC.

• For optimum performance, batteries should all be of the same brand, age and amp-hour capacity within a battery bank.
• Proper battery connections should be used, designed for high currents & long life. Connections should be tight and covered with petroleum jelly to prevent corrosion.
• Batteries produce explosive hydrogen gases during charging, so avoid sparks or flames. They contain corrosive chemicals.
• Utmost care must be taken whilst working with batteries.

Maintenance requirements vary by battery chemistry and configuration. Additionally, some maintenance tasks, such as adding water or equalization, require on-site manual operations and/or oversight, while charge regulation, voltage checks and related measurements can be automated via sophisticated charge controllers or battery management systems, which are a de facto requirement for lithium-ion batteries.

Lead acid batteries

Sealed lead-acid batteries, gel cells and AGM (Absorbed Glass Mat), are often referred to as maintenance-free because they don’t require watering or an equalisation charge. This makes them well-suited for remote or unattended power systems. However, sealed batteries require accurate regulation to prevent overcharge and over-discharge.

Lead-acid batteries should always be recharged as soon as possible. The positive plates change from lead oxide, when charged, to lead sulfate, when discharged. The longer they remain in the lead sulfate state, the more of the plate remains lead sulfate when the battery is recharged. The portion of the plates that become “sulfated” can no longer store energy. Batteries that are deeply discharged and then only partially charged on a regular basis often fail in less than one year. Always use temperature compensation when charging batteries to prevent over or under-charging.

NOTE: Battery warranties do NOT cover damage due to poor maintenance or loss of capacity from sulfation.

Check the electrolyte level in wet-cell, or “flooded” batteries, at least once every 3 months and top-off each cell with distilled water. Keep the tops of batteries clean and check that cables are tight.

Lithium batteries

These are usually maintenance free. However, to ensure correct operation all connections should be checked periodically and tightened to correct torque values where necessary as temperature variations can cause them to loosen.

Any monitoring or BMS software should be used to check for any irregularities in operation.