48V 13Ah SilverFish Lithium E-bike Battery For 350W 500W 750W Motor 624Wh power. It is bottom 4 pins connection. The discharging positive (+) is on the key and charging socket side, please make sure the polarity is not reversed from your old battery before purchasing. The size is 39cm11cm7.5cm(Length x width x hight), please make sure this size can be installed to your bike. Please mind the the red wire is positive +, the black wire is negative. Battery Type:Fish Lithium-ion. Rated Voltage / capacity: 48V / 13Ah. W: 3.26KG/3.66KG. L390W110H75 (inch):L154W43.5H29.5. Case Material: ABS+Aluminium alloy. Batteries combinations:13-S, 6-P. Component:Li(NiCoMn)O2. Recommend to use:200W-750W. Discharge Standard current:15A. Discharge Cut-off voltage:30V. Discharge cycle life:1000times. Discharge method :bottom discharge. Charging time :Standard 0.2C5A×5hrs. Charging time:Quick 0.5C5A×2hrs. Charge Max current:2A-5A. Fuse:Installation position:Inside on the PCB. Fuse:Diameter(mm):5. Fuse:Length(mm):30. PCB board Protection:Over charge, over discharge, over load and short circuit. BMS board Protection:BMS is used to supervise battery by measure its. Voltage, temperature, current and SOC (State Of Charge), give out alarm. Under wrong circumstance, cut off electric power link in severe. Situation in order to protect battery and make its life longer. Balance energy among batteries to make them more identical and expand. We guarantee: All items are 100% brand new, never be used & not refurbished. In our working hours will be resumed within 48 hours. Our aim is to provide Top Level Customer Service, your recognition will encourage us greatly and serve you better. We strive to keep all our customers satisfy. We strive to answer all questions and resolve any problems as quickly as possible. Our office time is: 9:00 a. To 6:00 p. (GMT +8) of Monday to Friday. Post office is closed on Sunday(GMT +8) and public holidays, so we will not sent items on Sunday and public holidays.