YROHGKPN BL1850B BL1840B BMS Protection Board, 18V Lithium Battery Charging Circuit with Indicator, DIY Replacement for Tool Battery

["Direct Replacement for BL1850B/BL1840B Battery Boards This protective circuit board is designed as a direct replacement for BL1850B and BL1840B lithium battery packs. Perfect for repairing or rebuilding your 18V tool batteries to extend their lifespan and restore reliable performance","Complete Charging Protection for Lithium Batteries Featuring advanced lithium battery charging protection technology, this PCB board safeguards against overcharging, over-discharging, short circuits, and overcurrent. Keep your DIY battery packs safe while maximizing their cycle life","Built-In LED Indicator for Status Monitoring Equipped with a convenient LED indicator, this battery protection plate allows you to monitor charging status at a glance. Know exactly when your battery is charging, fully charged, or experiencing issues for smarter battery management","Precise Fit for BL18V Tool Battery DIY Engineered with accurate design for a perfect fit, this circuit board is specifically made for 18V tool lithium battery housing DIY projects. Whether you're rebuilding old battery packs or creating custom power solutions, installation is straightforward and reliable","Quality Materials for Reliable Performance Crafted from high-quality printed circuit board materials, this protective board delivers dependable performance and easy installation. Please note: This listing includes only the protective board—batteries and casing materials are sold separately"]