Bestgo offers the "Preferred" series lithium ion battery packs to suit different kinds of applications. The chemistry of the battery pack consists of Lithium Iron Phosphate (LiFePO4) which is the safest li-ion battery. All battery packs are equipped with aluminum cases for strength and safety. They are light in weight, reliable in strength, with good thermal conductivity. They are also attractive in appearance with a rounded corner shape.
These Preferred battery packs are sealed to meet IP66 protection level so they can be used in many harsh conditions. To realize this design, Bestgo uses the most advanced cells which can offer superior performance that will generate much less heat than other competitor’s products. The Preferred packs feature passive cooling without a fan.
However, if the battery packs need to offer continuous high-power input and output (like within 2 hours charging from empty to full, or discharging from full to empty in 2 hours), and the surrounding temperature is high, please consider offering some air cooling or liquid cooling method to keep the battery pack within a reasonable temperature. If the battery pack is not overheated, it will have a long life.
The Preferred packs have handle(s) for lifting and carrying. In addition, they have an intelligent indicator to show the voltage, current, SOC and capacity etc. Red and black terminals with M8 screw holes build on top lid for power cable connection. There are 3 screw holes on each long side of the battery pack. Each screw hole has a size of M4*8. They can be used to fix the battery pack with bolts. Screw holes do not affect IP level as the end of hole is totally sealed.
Chemistry: Lithium Iron Phosphate (LiFePO4)
Battery Pack Dimension (L*W*H) and connector type: 12.25 * 10.2 * 9.0 in. (310 * 258 * 229mm) (metal case size)
Red and black terminals with M8 screw hole. Terminals have 18mm height above case.
Battery Pack Weight: 53 Lbs. (24 Kg)
BMS and Fuse: PCB BMS and fuse are built inside case. The fuse is 150A slow type.
Rated Capacity: > 100 Ah at C/3, 73°F (23°C) (Measured as 2.5V cut off at cell level)
Operating Voltage: 25.6 V (average) at C/3, 73°F (23°C); Working voltage range is 29.2 ~ 20.8 V
Charging Voltage: < 29.2 V at CC/CV charge mode (Can be changed to 28.8V for longer cycle life.)
Discharge Cut Off Voltage: 20 ~ 20.8 V (When any cell's voltage reaches 2.5V this protection will be triggered) (Set device (like controller) low volt protection much higher to avoid triggering this protection.)
Maximum Charge Current: < 50 A at 60 min, 23°C, 20%< SOC <70%; < 100 A at 5 min, 23°C, 20%< SOC <70% (Please consider heat accumulation inside pack if charging with a large continuous current.)
Maximum Discharge Current: < 120 A at 30 min, 23°C, 30%< SOC <100%; < 260A at 15s, 23°C, 30%< SOC <100%; < 320 A at 0.5s, 23°C, 30%< SOC <100% (Please consider heat accumulation inside pack if discharging with a large continuous current.)
Battery Cycle Life: > 3000 times at 80% DOD, C/3, 23°C (After cycles it can deliver > 75% rated capacity.)
Internal Resistance: 20 milliohms (DCIR test method, at 10s, 50% SOC)
Temperature protection for charging process: 0 ~ 5 °C < Sensor for cell < 52 ~ 58 °C (If inside sensor detects a temperature that is out of range, the BMS will shut the pack off.)
Temperature protection for discharging process: Sensor for cell: < 65 ~ 70 °C (If inside sensor detects a temperature that is out of range, the BMS will shut the pack off.)
Surrounded working condition temperature: Charge: 41 ~ 113°F (5 ~ 45°C); Discharge: -4 ~ 131°F (-20 ~ 55°C) (Suggested for charging: 50 ~ 104°F (10 ~ 40°C); Suggested for discharging: 14 ~ 113°F (-10 ~ 45°C)
Storage Temperature: 14°F ~ 104°F (-10°C ~ 40°C) (for < 3 months) Keep SOC at 40~60% for long term storage.
Note: Inside the battery pack, the temperature sensors are attached to the cells and a BMS. However the temperature measurements are not very accurate. As a result, the BMS may trigger protection at the certain range of temperature. Due to a passive cooling design which does not have a fan for cooling, please consider the heat accumulation inside the pack. When in a hot temperature please do not charge or discharge the battery pack with a big constant current, it may trigger temperature protection.