Battery Types

Lithium-ION phosphate batteries (LFP) are known to be safe, durable, long-lasting, and ideal for home or a garage-based solar panel battery bank. Because this type of battery does not house any form of cobalt, a known fire hazard, they are often considered to be one of the safest battery types to use for residential solar panel systems. They also do not need any type of ventilation or cooling systems, making them ideal batteries to be installed indoors as the solar panel battery bank of a residential home or larger building structure. This is one of the most commonly used battery types for residential solar panel system users that require daily energy cycling and are attached to the national grid.

Lithium nickel manganese cobalt oxide (NMC) batteries are another very safe power cell often used within residential solar systems. Just like LFP batteries, NMC units also possess a battery management system that diagnoses and monitors all the unit’s core functions. Unlike LFP batteries, these batteries possess nickel and manganese cobalt oxide mixed within their chemistry, allowing them to store much more energy than all other types of lithium-ion batteries.

Lead Acid batteries come in two varieties: Flooded Lead Acid (FLA) and Sealed Lead Acid (SLA). They are generally cheaper than Lithium ones but tend to be less efficient, won’t last for long and usually require regular maintenance.

In FLA batteries the plates are submerged in water which must be checked regularly and refilled every 1-3 months to keep them working properly. Falling behind on upkeep can shorten the life of the batteries and void the warranty. FLA batteries also need to be installed in a ventilated enclosure to allow battery gases to escape.

Sealed Lead-Acid (SLA) batteries come in two types, AGM (Absorbent Glass Mat) and Gel, which have many similar properties. They require little to no maintenance and are spill-proof.
It takes two lithium batteries to power a 5.13 kW system, but you would need 8 lead-acid batteries to do the same job. When you take the size of the entire battery bank into account, lithium weighs less than half as much.

Though the price of Lithium (ion or iron phosphate) is higher, it is much better value. It will last far longer and deliver more kWhs (units) during its lifetime. In most cases, lithium-ion batteries are the best choice because they hold more energy in a small space, discharge most of their stored energy and are highly efficient.

Nickel Cadmium is more widely used in the aircraft industry. Together with being almost maintenance free, they are very durable and can operate at extreme temperatures. However, because Cadmium is extremely toxic, it is banned in some countries which makes disposal more difficult; best used in large scale operations

Flow batteries are water based and rising in popularity because they have the longest lifespan at 30 years with low maintenance. They are more expensive owing to their larger size and their required size makes them harder to adapt for residential use.They can achieve a 100% DoD without damage and because the liquid inside is fire-retardant, there is no thermal runaway risk.