Victron Smart BMS 12/200 battery management system

Smart BMS 12/200 for Victron lithium-iron-phosphate (LiFePO4) smart batteries.

It is specially designed for 12V systems with a 12V alternator.

The Smart BMS 12/200 monitors and protects each individual battery cell within the battery (or battery pack) and will disconnect the alternator, charging sources or DC loads in the event of low battery voltage, high battery voltage or over temperature.

The dedicated alternator input provides current limiting and one-way drive from the alternator to the battery, so any size alternator (and starter battery) can be safely connected to the Smart Lithium battery or batteries.

The BMS is equipped with Bluetooth for monitoring and configuration, a remote control on/off socket, to turn off the BMS (and the system) via a remote control and a warning contact, to give a warning signal before the BMS disconnects batteries from the system.

Why you need a Battery Management System (BMS):
1. An LFP cell will be destroyed if the voltage across the cell drops to less than 2,5V.

2. An LFP cell will be destroyed if the voltage across the cell rises to more than 4,2 V. Lead-acid batteries will eventually also be destroyed when they are deeply discharged or overcharged, but not immediately. A lead-acid battery will recover from total discharge even after being left in a discharged state for days or weeks (depending on the type and brand of battery).

3. The cells of an LFP battery do not automatically balance at the end of the charge cycle. The cells of a battery are not 100% identical. Therefore, when recycled, some cells will be fully charged or discharged sooner than others. Differences will increase if the cells are not balanced/balanced from time to time.

In a lead-acid battery a small current will continue to flow even after one or more cells are fully charged (the main effect of this current is the decomposition of water into hydrogen and oxygen). This current helps to fully charge other lagging cells, thus equalizing the state of charge of all cells.

However, the current flowing through a fully charged LFP cell is almost zero, and therefore lagging cells will not be fully charged. Over time the differences between cells can become so extreme that even though the overall battery voltage is within limits, some cells will be damaged by over or under voltage.

Therefore, a LiFePO battery must be protected by a BMS that actively balances individual cells and prevents under- and over-voltage

Specifications