Chaowei Energy & Power Co.,Ltd is one of the leading lithium ion electric vehicle battery manufacturers in China,Website: , equipped with one of the famous brands, welcome to buy discount lithium ion electric vehicle battery, and you are also welcomed to check the price and quotation with our factory.Model: BN4820LK                48V 20Ah(2hr) Lithium Ion Battery ModuleChilwee BN Series Lithium Ion Battery Pack is designed based on MnNiCo Composite technology with excellent cycle performance and high safety.BN Series is mainly applied to electric bicycles, tricycles and other electric vehicles. The battery module is comprised of soft-packed battery cells in series and battery protection module is included to ensure supreme reliability.FEATURES• Modularized design and pefectly compatible to the electric bicycles which are using traditional VRLA batteries• \'Green\" and environment-friendly, no pollution to the environment during production and normal usage• Stable structure and simplified production process enables mass production and easy maintenance• Completely new protection design of water-proof, fire-proof, shock-resistance enable high safety• Professional protection module and BMS ensures the battery pack to be protected perfectly• High weight and measurement specific energy ensures the battery pack extremely long-voyage ability• Super long life supported by innovative technologies, high quality material and strict manufacturing controlSPECIFICATIONBattery Model No.BN4820LKMaterialMnNiCo Composite Material + LiMn2O4Nominal Voltage (V)48VNominal Capacity (C2, 25℃ )20AhBattery Pack Dimension (mm)290mm X 190mm X 80mm (L X W X H)Nominal Weight (Kg)7.1Kgs ± 0.1Charge Limited Voltage (V)54.6VContinuous Charge Current (A)4AMaximum Charge Current (A)10ACharging Mode (Constant Current/Constant Voltage)4A X 6.5hDischarge Cut-off Voltage (V)≥ 39VContinuous Discharge Current (A)≤ 20AMaximum Continuous Discharge Current (A)≤ 35ACycle Life at 100% D.O.D.≥ 800 CyclesCharge Port / Discharge PortCannon Plug / 3 Square Pin Plug : N-Positive, L-NegativeCapacity Retention Rate at 0℃≥ 90%Self-Discharge Rate (25℃)≤ 3% per monthTemperature CharacteristicCharging0℃ - 40℃Discharging-20℃ - 40℃Storage-20℃ - 40℃* All the technical data are for customer\'s reference only. This information is subject to change without any prior notice.Testing Condition,Method and Electric Performance 1) Unless otherwise specified, all tests are conducted at ambient temperature 23 ± 2℃, relative humidity 25%-85% and atomspheric pressure 80kPa - 106kPa2) Testing DevicesA) The accuracy of DC Voltage Meter shall not less than Class 0.5, and the internal resistance of Voltage Meter shall not less than 1KΩ/VB) The accuracy of DC Current Meter shall not less than Class 0.5C) The Temperature Meter shall has enough measuring range, and scale interval shall not bigger than 1℃D) The Timer for measuring time shall be with hour, minute and second, and the accuracy shall at least ±1%3) Standard Charging for Battery PackCharging the battery pack with DC stabilized power supply or charger at charging mode - Constant Current and Constant Voltage (CC/CV). The charge limited Voltage is 54.6V and charge current is 4A (0.2C) until the current dropped to 0.04A (0.02C)4) Standard Discharging for Battery PackCharge the battery pack as per Item 3), and then discharge the battery pack with 10A (0.5C) to the battery over-discharge protection voltage.5) Battery Pack Capacity TestDischarge the battery pack as per item 4), and recording discharge time (hours), capacity (Ah) = 10A (0.5C) * discharge time (hours)6) Electro-Chemical PerformanceTest ItemTest MethodTechnical RequirementNormal Temperature Discharged CapacityBattery Pack is charged as per Item 3), and then discharged as per Item 4), record the battery pack\'s capacity≥100% Nominal Capacity-20℃ Discharged CapacityBattery Pack is charged as per Item 3), and then stabilizing at low temperature cabinet at -20±2℃ for 6 hours, and then discharge the battery pack as per Item 4), record the battery pack\'s capacity.≥85% Nominal Capacity55℃ Discharged CapacityBattery Pack is charged as per Item 3), and then stabilizing at high temperature cabinet at 55±2℃ for 6 hours, and then discharge the battery pack as per Item 4), record the battery pack\'s capacity.≥95% Nominal CapacityCharge Retention CapabilityBattery Pack is charged as per Item 3), and then leave it for 28 days at normal temperature or for 7 days at 55℃， then stabilizing for 5 hours at normal temperature, then discharge battery pack as per Item 4), record the battery pack\'s capacity.Charge Retention rate ≥95%Cycle LifeBattery Pack is charged as per Item 3), and then stabilizing 10 minutes, and then discharge as per Item 4). Repeat the cycles. In every 25 cycles, check the battery pack\'s capacity as per standard discharge, when the battery pack\'s capacity is less than 60%, test stopped.≥ 800 cyclesTechnical Curves48V 20Ah Lithium Battery Pack 0.2C Charge Characteristics Curve48V 20Ah Lithium Battery Pack 1C Discharge Characteristics Curve48V 20Ah Lithium Battery Pack Discharge Characteristics Curve at -10 Degree C48V 20Ah Lithium Battery Pack Discharge Characteristics Curve at -20 Degree CBattery Pack Operation Instruction1) After fully charging of the battery pack, the battery pack shall be installed in the frame of the electric bike.2) The position of \"+/-\" polarity of the discharge terminal port at each electric bicycle is different, so please check and confirm the position of the polarity before connecting the battery pack to the electric bicycle.3) Turn on the battery power lock (turn your Key to \"On\" position). Check if the bicycle\'s power indicator is normal, if it is normal, run it normally. If there is anything abnormal, please contact your electric bicycle dealer for technical resolution.4) Lithium Ion battery is environment-friendly and smart battery, and there is no \"Memory Effect\". So lithium ion battery can be recharged at any SOC (stage of charge) without any damages to the battery. During the charging, plug-in the charger\'s charging port to the battery pack\'s charging port, and charging can be stopped when the charger indicator turns to green.5) The optimum charging method of lithium ion battery is to recharge the battery pack at the time when the battery pack\'s capacity has not yet been discharged fully. In case the battery pack\'s capacity has been discharged 100%, the battery pack must be recharged within 48 hours, or else the battery pack may be permanently damaged because BMS system also comsumes electricity from battery pack which cause serious overdischarge to the battery pack.Battery Pack Storage and Transportation1) StorageIf the battery pack has to be stored for a long period (1 months above), the battery pack must have retained 50% of the capacity before storage (recharge the battery pack by equipped charger for 2-3 hours after each fully discharge), and must stored at dry, ventilated place. The battery pack must have been recharged for 1-2 hours in every 3 months.Battery pack and charger must be stored at clean, dry and well-ventilated warehouse, and they must be kept away from corrosive material, source of iginition and heat.Battery pack shall be installed vertically and \"upside down\" is not allowed, and mechanical impulse and heavy load pressure shall be prevented.2) TransportationBattery pack and charger must be packed well before sending for shipment. The packed goods can be shipped by road, railway, vessel, and airplane. The SOC (state of charge) of the battery pack shall be at between 40-60% during transportation, and violent mechanical pulse, sun exposure, rains, upside down are prohibited during transportation.The battery pack must be well treated during uploading and unloading.Warning of Battery in UsePaper carton for per bank battery, Then stripped with  plstic pallet.7-10 DaysOur ServicesChilwee products have already been distributed in all over world, and local service facilities are being deployed in each region. Chilwee is committed to provide complete services including technology training, warranty replacement service, fault analysis trouble-shooting, battery maintenance service and battery disposal service, etc.Company Information