# 4S, 16.8V balancing module

> Balancing module for 4 Li-Ion cells in series (4S, 16.8VDC), connected to the balance port. Brings the cells to equal voltage during charging, limiting via an integrated resistor cells that reach 4.2VDC, with a balancing current of 66mA per cell. Provides no charge/discharge protection, intended for use alongside a BMS without balance function.

- Page: https://sigmanortec.ro/en/4s-168v-balancing-module
- Price: 9.86 RON
- Availability: Out of stock
- Reference: 33284 · EAN: 5945386783923
- Category: Electronic components > Modules for Batteries > Charging and Balancing Modules
- Specifications: Load voltage: 16.8VDC; sway: Yes; Number of cells: 4S
- Package (shipping data): 0.002 kg
- Updated: 2026-09-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 03:25 (Europe/Bucharest)

## Description

Allows automatic balancing of 4 Li-Ion 3.7V cells in series, by connecting to the 4S balance port, brings the cells to the same voltage when charging and is ideal with a BMS without balance function, limits cells reaching 4.2V through the integrated resistor to let the others recover, balance current 66mA per cell, for 16.8V.
The module for balancing 4 3.7V batteries in series. By attaching the balance port of the battery in 4S configuration to this module, the individual cells will be charged at the same voltage. the module works correctly together with a BMS that does not have a balance.
When the battery is charged, the module detects the cells that have reached the 4.2VDC threshold and blocks, with the help of the integrated resistor, the charging of those cells while the uncharged cells still catch up with the charged ones.
The balancing plate does not have any kind of protection when charging or discharging. A BMS board is needed for protection.
If there are differences in internal resistance between the cells, there will also be a difference in tension between the equalized cells. For example, at a difference of 5 milliohms between the cells, the final voltage will differ by up to 0.03, which translates into cells charged at slightly different capacities. For this reason, it is good practice for the cells to have an internal resistance as close as possible.
Specifications:
Compatible batteries: 4S, 16.8VDC, lithium
Individual cell maximum voltage: 4.2VDC
Balanced current per cell: 66mA