Cylindrical lithium batteries (18650, 21700, 26650) offer mature processes, high consistency, and cost efficiency, with flexible series-parallel configurations from tens to hundreds of watt-hours. Backed by proven assembly expertise and in-house BMS design, XYJC builds high-reliability custom packs for power tools, e-bikes and scooters, portable energy storage, service robots, and security and lighting equipment — supporting high-rate discharge, wide temperature ranges, and multi-level safety protection.