Bay Valley PartsReplacement Laptop Battery MR90Y XCMRD for Dell Inspiron 14 14R 15 15R 17 17R 3521 3721 5421 5521 3421 5721 Battery type: Li-ion; Capacity: 28.8Wh; Cells: 3-cell; Voltage: 11.1V;Capacity:2600mah. Quality: Grade A cells ensure fast charges and low power consumption. Origin: 100% New from Manufacturer. Up to 500 recharge cycles over the life of the battery;1 Year Warranty Guaranteed. Protection: Built-in circuit protection, overcharge protection, over voltage protection ensures both safety and stability;Safety: Worry-free, products are passed CE-/FCC-/RoHS-Certified. In case if battery is not charging properly or is not working, please remove the battery and clean the battery connectors by using the toothpicks and then replace the battery. Please discharge all the remaining power and recharge it for continuous 8-12 hours, and then discharge and charge 8-12 hours again. Please repeat this for 2 or 3 cycles so that it can be activated completely.