3000MAH is the amount of energy in the battery. That means it can be discharged for one hour with a current of 3000MAH.
The battery must have a voltage, and 36 volts means 36 volts for this type of input appliances. If you use an appliance with a low voltage rating, you may burn the device. Appliances with high input voltage will not be able to carry the device.
Battery (Battery) refers to the electrolyte solution and metal electrodes in order to generate current cups, tanks, or other containers or composite containers of part of the space, can be converted into chemical energy into electrical energy device. Has a positive pole, negative pole.