A Battery Management System, or BMS for short, is used to protect your battery during charging and discharging.
During charging, the BMS will monitor the voltage of all of your cells and balance the cell groups to ensure they are charged equally.
During discharging, the BMS will monitor the voltage of all of the cells, as well as the entire pack voltage and the discharge current. If the BMS determines that any of its preset limits have been passed, such as the battery draining too low or an unsafe amount of current being pulled from the battery, the BMS will cut power to the battery to protect it from damage.
Most BMSs are hard to install because you have to solder on the wires yourself. Our BMSs come with 6″ high quality silicone wires already connected, making it much easier to install. The discharge wires are 12 AWG silicone wire and the charge wire is 14 AWG silicone wire.
The BMS is easy to install, but will require that you are decent with a soldering iron if you want to extend the wires. The wiring diagram for this BMS is shown below, and you can read an article showing you how to install a BMS on your VRUZEND kit here. Please make sure you read the instructions in that article so you can install your BMS properly. Note: it is important to connect the B- wire (the thickest black wire) first, and then continue connecting the rest of the wires, as described in the instructional article.
This BMS is for a 52V battery, meaning 14 groups of li-ion cells in series. A 52V battery is commonly used in place of a 48V battery to achieve a slight increase in power.
Note: Our BMSs have recently been updated with an external temperature sensor. This is a pair of white wires with a temperature sensor on the end. It is simply an extra safety feature and the sensor can be placed anywhere in the battery pack for temperature monitoring to ensure BMS cutoff if the safe limit has been surpassed.
Number of cells: 14
Maximum rated discharge current: 30 A
Charging voltage: 58.8 V
Maximum rated charging current: 15 A
Balance current: 50 mA
Operating temperature: -5ºF to 113ºF (-15ºC to +45ºC)
Board dimensions: 4.25″ x 2.33″ x 0.33″ (10.9 cm x 5.9 cm x 0.9 cm)
Note: this BMS is designed for lithium-ion cells, and will not work for LiFePO4 cells.