Lithium-iron-phosphate (LiFePO4) has been widely adopted by industry. It is very stable, without risk of fire or explosion, even with an elementary BMS.
This battery is also characterized by the large number of allowable charge-discharge cycles, around 3,000 discharges against a few hundred for most batteries sold (lithium or lead).
It also has a particular characteristic, a sort of reverse memory effect: the less the discharge, the greater the number of cycles, which makes it particularly insensitive to microcycling.
AGM batteries are often written as VRLA (Valve Regulated Lead Acid). Which means the battery is waterproof. Gas will escape through safety valves only in the event of overload or element failure.
The gel battery is a lead battery with gel electrolyte. Invented in the 1950s in Germany, this type of battery created by Sonnenschein is one of those with an optimal lifespan compared to so many other batteries. More exactly, it is 8 times more resistant than a traditional battery. It is also the most used for storing solar energy.