New EU Regulation for Batteries

04 May 2023

REGULATION OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL concerning batteries and waste batteries, repealing Directive 2006/66/EC and amending Regulation (EU) No 2019/1020

This document describes in abbreviated form the content of this EU regulation with regard to the GENEREX products BACS, SMARTBATTERY and SMARTLOGGER and their use in stationary energy storage systems.

Demand for batteries is forecasted to increase 19-fold in the coming years;

Such exponential demand lends increasing strategic weight to the industrial and stationary battery markets. Significant scientific and technical advances will continue to be made in the field of battery technology, and in order to best shepherd such advances towards a sustainable and positively lasting impact it has proven necessary to create a harmonized regulatory framework for the entire life cycle of batteries placed on the market in the EU.

For this reason, on December 10, 2020, the European Commission published a proposal for the new Battery Regulation with the goal of repealing the Battery Directive 2006/66/EC and amending Regulation 2019/1020.

The whole documentation can be found here, for further reading:-> EU_BMS <-

Particularly of relevance is Article 14, Chapter III, wherein the role of a Battery Management System is outlined. As stated in the legislation documentation, a 'battery management system' is an electronic component that monitors and controls the electrical and thermal functions of the battery, manages and stores data on the parameters for determining the ageing state and expected lifetime of batteries, and communicates with the device in which the battery is installed. According to the EU Council, a “battery management system” must fulfill or otherwise provide necessary data measurement according a framework of key parameters.

BACS already provides a working, proven system in almost all respects otherwise required by this directive for 2026!

The following list (in short form)

The requirements of the EU  = are shown in in black letters
The solution provided by BACS = are given in blue letters

Battery Capacity

1. Remaining Capacity
BACS: As of 2022 BACS is able to calculate and display individual cell/battery capacity in real-time.

2. Remaining Battery Efficiency – ( "Round Trip Efficiency"):
BACS VIEWER illustrates and displays the difference between two discharges.

3. Battery Capacity
BACS is the only BMS on the market which displays the battery capacity against the AC / DC resistance (and includes Battery Current and Temperature in the Capacity measurements).

4. Total Capacity Loss
BACS: Through use of the BACSVIEWER software such a comparison is straightforward and readily accessible.

5. Remaining Power Capacity and Power Loss
BACS: Ensures a 100% state of charge for each battery thus providing the prerequisite for comparability of discharge tests. The long term data as provided in tandem with BACSVIEWER allows for a quick and efficient determination of lifespan power loss.

6. Autonomy time
BACS provides a calculation of autonomy time based on the relationship between UPS input, battery current, battery voltage and temperature and impedance.

7. Battery Capacity determination by discharge tests
BACS measures and indicates the battery capacity once per second during discharge, and such a discharge test can be carried out without the risk of unnoticed damages of cells/batteries


1. Ohmic Resistance and/or Electrochemical Impedance
With BACS, this is indicated by the “RI” reading; the trend line as indicated in the BACS VIEWER shows the expected lifetime.

2.    Resistance
BACS: The difficulty is that in given high voltage string applications (UPS), the cells/blocks tend to deviate from the ideal float charge voltage and differences of 2V and more are frequently found within the string. Such a situation makes it impossible to compare the AC/DC resistance measurements under float charge. BACS balances the voltage differences so that all cells/batteries are equal, not differing more than 0.01 Volt from one neighboring cell/battery to the next. This allows for a comparison between the AC/DC resistance values, and makes the use of such measurements useful for diagnostic procedure.  

3.    Baseline RI
BACS offers freely configurable threshold settings for RI resistance, based on absolute values in mOhms, based on Dynamic values, or based on a given set of “Base Line” values, depending on what best suits the installation.


1. Temperature impacts on the battery capacity
BACS’ Battery Capacity display is based on this capacity compensation per degree Celsius and adds this factor into its calculations of Battery Capacity.

2. Temperature influence on battery life span
BACS records the battery temperature over the long-term and the average temperature is shown so that the user knows what the life-span for his or her batteries should be.

3. Temperature influence on Battery self-discharge
BACS shows the trend of the battery voltages over time; also measured is the historical Equalization/Balancing activity in %. If balancing is indicated at 0% but the charger is running, this would indicate either that the battery breaker may be open and the self-discharge is draining the battery – OR – the temperature is too high so that the self-discharge is greater than the current from the charger, which has to be altered to compensate the behavior of the temperature increase or aging effect of the batteries.

4. Temperature influence on Battery charge current
At a given constant voltage, the float current passing through a fully charged stationary battery increases progressively with increasing battery temperature.
BACS shows this increasing current and balances this out within the limitations of the system. Typically, this is enough to avoid battery damages because the UPS or charger automatically decreases the charge voltage (and the current) if the external sensor reads higher temperatures.

5.    Influence of ripple currents on battery temperature
BACS monitors and indicates AC and DC ripple currents, allowing for corrective action before such an effect causes an increase in battery temperature.

6. Temperature differences due to a poor design of a battery installation can cause battery faults
BACS is able to balance the voltages within the string, whether the voltage differences come from the poor layout or from chemical differences within the batteries. This ensures that performance reduction owing to temperature differences due to poor design in the battery layout is otherwise negated.

7. High temperature differences for a time period > 24h can cause a thermal runaway
BACS: If the charger is setup correctly and BACS can balance the voltage differences due to thermal or electrical differences, the risk of such a thermal runaway under float conditions can be dramatically reduced or avoided entirely.

8. High Temperature
BACS cannot prevent overheating of batteries due to room ventilation issues, but BACS can warn the user about such conditions and, if connected to the appropriate automation interfaces (GXRAUX), it can automatically switch on Air conditioning or trigger to open windows, fans, etc. to solve the situation.

9. Real Cooling Demand
BACS: The cooling demand is determined by the difference recorded by BACS; it generally increases with age due to the increased current consumption during trickle charging and thus indicates an increasing risk of thermal runaway.

Battery Current

1. Float current – AC component (super-imposed ripple current)
The ripple current (AC component) is generated by the charger and/or by the load (e.g. inverter) and is super-imposed to the DC float current. This ripple current does not contribute to the battery charge; it only generates additional heat. A high super-imposed ripple current and a DC current near zero will lead to discharge and deterioration of an effected lead-acid battery. It should be noted that the float current at the end of life of a VRLA battery doubles in comparison to a new battery.
BACS: Such an increase of the float current can be visualized with BACS and can trigger an alarm. Alarm levels for DC float currents can be set within the BACS configuration to avoid a malfunction of the battery due to increased water loss, excessive shedding of active material or the promotion of internal short circuits and excessive heat evolution, which in the end may cause thermal run-away.

2. Maximum ripple current
Under float conditions, the super-imposed effective ripple current at frequencies >30 Hz should be limited. Appropriate precautions should be taken in order to avoid dangerous voltages and short-circuits at and through the sensing leads. Fast fuses or current-limiting resistors shall be inserted into each sensing lead
BACS is the only BMS on the market with 2 high voltage fuses featured within the sensing leads.

Flame retardant/low smoke and fume or acid resistant insulation may under certain circumstances be required for the sensing leads.
BACS utilizes halogenfree cables and fire retardant material for housing and components to avoid damages caused by such dangerous voltages – except the fuses – and can disconnect itself from the system to trigger alarms about the blown fuse and ripple voltage.

3. Load Current Share
BACS shows current values per string and allows to set thresholds if these values get imbalanced; should such an imbalance occur the operator can thus be informed accordingly.

4. Energy Flowthrough
This figure is measured through use of the new BACS Current Sensor Type CSHxxxF and CSHxxxD. The BACS Current Sensor in tandem with the measurement data of the BACSVIEWER is able to display the trend line of the aging battery or cell.

Battery Health and Sustainability

1. Ongoing Development of the Self-Discharge Rate
This can be identified by the otherwise naturally decreasing autonomy time of a given battery or cell. The older the batteries become, the higher the self-discharge rate. To determine the exact development curve, the trickle charge must be switched off while the given cell or battery is in the fully charged state.
The BACS and SMARTLOGGER / SMARTBATTERY measured values will show the self-discharge rate after a few days. This must be compared with the self-discharge rate in new condition.

2. Date of Battery Manufacturing and Commissioning
this is defined and archived for up to 10 years during commissioning of BACS and SMARTLOGGER and SMARTBATTERY.

3. Data Access
clear unobstructed access to the aforementioned parameters be available for analyzation at any time in order to assess the residual value of the battery, to facilitate battery reuse, repurposing or remanufacturing, or to make the battery available to independent aggregators operating virtual power plants in electricity grids.
BACS, SMARTLOGGER, SMARTBATTERY provides the data in various formats to make it analyzable by recyclers.

4. Long-term Data Recording as applies to Storage and Transport Conditions
The SMARTBATTERY or SMARTLOGGER from GENEREX provides the desired long-term data – from “the cradle to the grave” – thus allowing for precise control of operating and storage conditions for the complete life cycle of a given battery unit.

5. Documentation Availability
Documentation must be provided for indicating the health and functionality of a given battery or cell. The economic operator who wants to perform the recycling must be provided with a document for the evaluation or testing of the aging condition.
SMARTBATTERY, SMARTLOGGER and BACS record and subsequently provide the required information for documentation.

6. Battery Passport
the EU requires that by January 1, 2026, every industrial battery and traction battery placed on the market must have an electronic identification file ("battery passport"). Each battery will have its own battery passport with individual identification and data on the producer, battery type, batch or serial number, date of manufacture, date placed on the market, chemistry. The battery passport is linked to the information on the basic characteristics of each battery type and model, which must be stored in a non-volatile memory and made available online.
BACS, SMARTLOGGER and SMARTBATTERY are already able to provide all the data required for a "battery passport" in a permanent and accessible format.

From 2026, these regulations are mandatory to be applied to all battery management systems

Even now, in 2023, BACS already fulfills these “future” requirements and is the only system made in Germany / made in USA which qualifies for the strict EU requirements for operation within high security IT systems.