4S 40A Lithium Battery BMS Balance Module - Enhanced Version

Product Description:

The 4S 40A Lithium Battery BMS Balance Module - Enhanced Version is designed to provide comprehensive protection and balancing for lithium batteries in various applications. This module supports a range of features to ensure the safe and efficient operation of your battery system.

Specifications:

• Charging Voltage: 16.8V - 17V
• Maximum Voltage Protection: 4.25V - 4.35V ± 0.05V
• Minimum Voltage Protection: 2.3V - 3.0V ± 0.05V
• Operating Current Range: 0-20A
• Peak Load Current: 34-40A
• Leakage Current: 30uA
• Short Circuit Protection
• High Charge Protection
• Over-Discharge Protection
• Dimensions: 44mm x 55mm x 4mm
• Weight: 8.8 grams

Notes:

• Note 1: This product is suitable for motorized devices (such as drills) with a nominal operating power of 170W or less.
• Note 2: If the drill operates when the batteries are connected directly but does not work when the output is taken from the BMS circuit, the issue may be that the instantaneous current provided by the batteries is too low. Motors require a significantly higher current at startup. When the batteries try to meet this current demand, their voltage may drop below the threshold, causing the BMS circuit to cut off the output. This indicates that the BMS is performing its function. You should consider using batteries with higher current capabilities or adding batteries in parallel. Upgrading to a higher current BMS will not resolve the issue.
• This Enhanced Version of the 4S 40A BMS Battery Module is specifically developed for motor applications. Batteries should be charged within limited current ranges to prevent shortening their lifespan. Rapid discharge or charging of high current can damage the batteries. Although BMS products may appear to charge the batteries, they do not control the current. Proper charging requires using a power source with current control along with the BMS module. The charging current should be around 1/10 to 2/10 of the battery capacity. Avoid very high current charging or discharging as it will reduce the battery life.

Question:

Q: Does it stop charging when fully charged?

A: Generally, these modules are not designed to stop charging when full. However, they have high voltage protection, so if one cell reaches 4.2V, it will cut off the charging process. This means that the module does have a charging stop function, but note that if one cell reaches 4.2V, charging will stop even if other cells are at 3.8V. Therefore, it is recommended to individually charge the cells to 4.2V before connecting them to the BMS to ensure they remain balanced. The cells should have the same production year, brand, and model to maintain balanced voltage and ensure a healthy charging process.