Active Battery Optimizer

Technology by Tesvolt

The Active Battery Optimizer (ABO) is a technological innovation “Made in Germany” by TESVOLT. The ABO not only optimizes the cells within the battery modules, but also the individual battery modules in relation to one another. This process is the only one of its kind worldwide and, for the first time, ensures that an investment in a modular lithium storage system is both safe and sustainable. The ABO is located on the front of each battery module.

Why is a battery management system (BMS) important?

The cells in a battery system age differently depending on a variety of factors. Cell ageing can lead to differences in capacity and internal resistance, as well as variations in leakage currents. This affects both charging losses and capacity, and thus has an impact on the voltage of each individual cell. On the other hand, excessive charging reduces the service life of the cells even further, quickly resulting in an avalanche effect if the problem is not rectified...

Cell monitoring and balancing systems are able to detect such differences in battery systems and correct them on a continuous basis. This process significantly increases the lifespan of individual cells.

Balancing methods

Comparison of methods Passive Active (unidirectional) Active Battery Optimizer
Procedure “Letting off” excess energy through resistance Distributing energy from one cell to another (unidirectional) Controlled distribution of energy across individual cells (bidirectional)
Losses high medium low
Efficiency 0 % 70-91% > 92 %
Costs niedrig high high
Maximum balancing current (without cooling) 0,05 A 3 A 5 A
Balancing period high medium low
Heat generation high low low
Cell protection and safety good good very good

Passive balancing:

Cells with excess voltage are discharged using fixed or selectable bypass resistances. Electrical energy resulting from the different states of charge is converted into thermal energy and lost.

Active unidirectional balancing (power pump or “charge pump” method)

Two transistor switches (MOSFET) and a choke are used to “pump” excess charge from one cell to the next. Since only the controlled discharge of circuits is permitted in this process, it is also referred to as unidirectional active balancing. However, charge can only be distributed between the cells in one direction here.

Active Battery Optimizer (TESVOLT)

In contrast to unidirectional balancing, here, each cell can be charged by or discharged into all other cells in a battery module. This allows the battery system to be balanced quickly and efficiently.

The TESVOLT battery management system

TESVOLT’s Active Battery Optimizer ensures that battery cells are always charged and discharged in an ideal way. The optimizer monitors the temperature, voltage and state of charge (SoH & SoC) of each individual cell or module and controls them within the battery system.

This efficient distribution of energy means that only 3 W (with TS 48V) and 5 W (with TS HV) are consumed by the storage systems in standby mode (battery cabinet incl. batteries and ABO). This prevents unnecessary heating of the system, which would in turn require a cooling system.

The process significantly increases the service life of individual cells and, thanks to software and hardware-based shutdown mechanisms (dual redundant), sets new standards in cell protection and safety.

The TESVOLT BMS is primarily made up of two components – the Active Power Unit (APU) and the Active Battery Optimizer (ABO), which are each connected to a battery module.

BatMon cell monitoring

Thanks to the innovative Active Battery Optimizer and comprehensive monitoring of the storage systems down to cell level, TESVOLT is able to provide its customers with software that can visualize the state of health (SoH – and voltage) and state of charge (SoH) of each individual cell.

Replace and upgrade batteries at any time

Our TS 48 V and TS HV 70 storage systems not only offer flexible configuration options at the moment of purchase – thanks to innovative Active Battery Optimizer technology, their capacity can also be expanded years later.