[How to charge safely: 1. Connect the wall charger to AC socket first and the led of the charger will light green. 2. Then connect the charger with battery. Will not charge? Please contact seller immediately to replace a new charger. "Modle: NB7102. Capacity: 25.9V 2.5Ah or 3.7V/17500mAh. ( Its just a different way of calculating actually the same capacity. )Total 64.75Wh." Output: DC1 (5521): 29.4-21V/3A DC2 (4017): 19.5V/3A USB-A: 5V/2.4A 12W Max. USB-C: 5V/3A 9V/3A 12V/3A 12V/3A 20V/3A 60W Max. Compatible with most Laptops Notebooks LED strip light products CCTV Camera LED Panel Modem Speak Car DVR Router etc. We Provide 12 Kinds of Connector for Most of the Popular Laptops please Make Sure the Connector Fits for Your Laptop before purchasing.]