21700 40T 3.6V 4000mAh Lithium-Ion Battery
High-capacity 21700 lithium-ion cell with stable 3.6V output and 4000mAh energy density, ensuring extended runtime for power-hungry devices. Premium NMC chemistry enhances thermal stability and cycle life, supporting 1000+ charges at 80% capacity retention. Precision-built with ultra-thin 0.1mm electrode layers and laser-welded terminals for minimal internal resistance (＜15mΩ). Includes multi-protection PCB against overcharge/overheat. Ideal for high-drain applications: electric tools, vaping mods, solar storage, and DIY power banks. Bulk orders available at wholesale-exclusive pricing—global shipping with guaranteed lowest rates.