Which type of battery should I use?

We recommend you to use VRLA, deep cycle or GEL batteries which will give you several hundred complete charge/discharge cycles, these kinds of battery are sealed so that inverter/UPS can be located with any direction and it does not void any poison gas during charging or discharging, but if you use vehicle starting batteries, they can not be charged or discharged smoothly, and they will wear out after about a dozen charging or discharging cycles.