noeifevo 21v 5a lithium ladegerat fur 5s 18 5v li ion lipo batterien kuhlventilator automatischer abschaltung redDue to some batteries with M25 charging connectors that have integrated charging protocols, our charger cannot support batteries with built in charging protocols. Please confirm with the battery supplier before purchase if the battery has an integrated charging protocol. For M25 (2+1+5) and M25 (2+4), the standard polarization is 1+ for positive and 2 for negative. If you require a different polarization, please let us know. Contact options: You can