A battery box sealable against moisture and oxygen ingress and liquid electrolyte egress. The battery box includes a first end, a second end opposite the first end, and sidewalls extending between the first and second ends to define a chamber for housing a number of rechargeable lithium battery cells. The first end and the sidewalls are metallic and have a substantially moisture and oxygen gas impervious joint between them. The second end is of a metal plastic laminate joinable to the sidewalls by a joining medium to form a substantially moisture and oxygen impervious joint therebetween. The second end has electrical connectors extending through it which enable substantially moisture and gas impervious connection to be made between current collectors of the lithium battery cells and the outside of the battery box.