Battery apparatus and assembling method thereof

A battery apparatus, comprising a first extension member, a second extension member, a separator and a plurality of battery modules, wherein the first extension member and the second extension member are arranged as partially overlapped to intersect each other and enclose a plurality of chambers, each chamber is provided with a battery module of said plurality of battery modules, the second extension member is segmented by the first extension member and each of the segments is provided with one separator, the separator is in contact with the battery module, and the separator and the first extension member are on the same side of the second extension member,

• wherein each of the separator is arranged on the second extension member at intervals along an extending direction of the second extension member and is independent of each other,
• wherein the battery apparatus further comprises a box body framework, and the box body framework comprises four frames forming surrounding walls of a box body,
• wherein the four frames are connected by non-welding,
• wherein an extending direction of the separator is the same as the extending direction of the second extension member, and at least one end of the separator in the extending direction is insertion-fitted with the first extension member,
• wherein the first extension member is provided with a positioning protrusion at a portion where the first extension member intersects with the second extension member, an end portion of the separator is provided with a slot, and the slot of the separator is inserted into the positioning protrusion of the first extension member.