Elite Acoustics Engineering produces Battery Powered Acoustic Amplifiers, Battery Powered PA Amplifiers or PA monitors are using two different type of batteries,
LifePO4 batteries have much longer shelf life then the SLA (Shielded Lead Acid) type of battery and is consider the safest type of Lithium battery. LifePO4 batteries can also supply much more current then the SLA type battery enable for a higher wattage amplifier. While the 12V9A SLA battery (used on our older generation amplifiers) can supply about 3A of maximum current, with the LifePO4 design we incorporated, 10A or higher can be achieved for our Amplifiers.More details on LifePO4 battery can be found on this link. LifePO4 battery.
SLA is available widely at a very reasonable price and it is very stable.