Safety and Environmental Protection: The battery core uses lithium-ion environmental protection materials, which not only has stable battery performance, but also built-in overvoltage, overcurrent, overload, short circuit protection, and temperature protection. Safe Lock & Led Battery Level Light: The bike battery made of aluminum alloy. The bike battery pack have ON/OFF Switch/ Portable Handle, Power Level Display, Key lock. 3 LED power indicator, each of which represents 33% power. Fit for Motor: 250W 350W 550W Battery Weight: 3.5/4/4.5/5KG Battery Size: 390*110*75mm Voltage: 36V Rated Capacity: 8Ah, 10Ah, 13Ah, 15Ah Charging Voltage: 42V Charging Time: 5-7 hours Charge Cycles：≤1000 Battery Cell Type: Lithium ion Working Temperature: -20℃～60℃ Package Included: 1*E-bike battery 1*Battery Manual 1*charger Storage: Store the battery in a cool and dry place (preferably between 0 and 30°). Do not place the battery near a heat source. In the winter when the temperature is below zero, the battery performance will be reduced, and the battery needs to be charged and stored at room temperature. Charge: Charge the battery once there is a chance to charge it, don't wait until the battery is dead. This can better maintain the battery.