The primary goal is to find a second use for the batteries from electromobility after they have been used in the vehicle (second-life use). For example, as energy storage for solar power or wind energy. When testing the remaining capacity, the battery is first fully charged and then discharged in a controlled manner. The capacity (SOC) and state of aging (SOH) are measured and the energy is fed back into the power grid with an efficiency of over 96%.

The bidirectional programmable DC power supplies from EA Elektro-Automatik are ideally suited for this process.

After the second-life cycle, the rechargeable batteries are subjected to final recycling. This process attempts to recover as many components of a lithium-ion battery as possible as raw material for new batteries. Before the batteries are disassembled into their individual parts, they must be fully discharged. This is done in order to avoid the risk of contact-hazardous voltage or fire and to use the residual energy still stored in the battery.

EA Elektro-Automatik’s regenerative electronic loads are a very efficient solution for this purpose.

The potential uses of second-life batteries from electric vehicles are many and varied. The applications range from home storage, emergency power supplies and power buffers to energy storage for solar power or wind energy.

For this application, it makes sense to use bidirectional laboratory power supplies for further investigation. With only one device, it is possible to test whether older batteries from electrically powered vehicles can still be used in other applications. If these applications are predominantly static and if the residual capacity is sufficient, these batteries will find their second-life use e.g. in stationary energy storage systems.

In this test, the battery is first fully charged with the bidirectional power supply and then discharged in a controlled manner with the same device. The capacity (SOC) and state of aging (SOH) are measured and the energy is fed back into the power grid with an efficiency of over 96%.

1 – High efficiency and higher safety when testing the battery capacity

Bidirectional programmable DC power supplies from EA Elektro-Automatik ensure the maximum possible charge and discharge of the batteries. With precise tests, detailed data about the remaining capacity is provided for the DUT.

2 – Amortization through power regeneration

The bidirectional programmable DC power supply from EA Elektro-Automatik takes its energy from the connected battery during the discharge process and converts it into AC voltage with an efficiency of up to 96%. This is then fed back into the local power grid and reused, thus amortizing the purchase price via reduction of electricity costs.

3 – Economy through time savings

The time saved in charging and discharging the lithium-ion batteries using the high input powers of up to 15kW in 3U enclosures or 30kW in 4U enclosures increases cost-effectiveness. In addition, the devices can be combined to form high-performance switchgear cabinet systems with a total output of up to 1.92MW.

4 – High flexibility in use

Versatile and flexible: Due to true autoranging capability of the device series from EA Elektro-Automatik, battery storage systems with different system voltages can be charged and discharged with only one bidirectional programmable DC power supply. For example, full power is available with one device for both a 400V and 800V system.

In order to make the recycling or reusability of lithium-ion batteries economical, all processes must run with maximum efficiency. Since lithium-ion batteries and lithium-ion polymer batteries should never be fully discharged during their service life, it can be assumed that most batteries end up for disposal with residual capacity. Before the batteries are subjected to the actual recycling process, they must be fully discharged.

Disadvantages of conventional battery discharging

• The batteries or accumulators are not completely discharged in the process
• Batteries that are not fully discharged are dangerous (High Voltage, fire hazard)
• The residual energy is consumed needlessly instead of being returned to the power circuit
• The discharging process takes longer and is inefficient

1 – High efficiency and higher safety during discharge

The complete discharge of battery storage means higher safety in the recycling process. EA Elektro-Automatik’s electronic loads guarantee the complete discharge of batteries with a high discharge capacity.

2 – Amortization through power regeneration

EA Elektro-Automatik’s regenerative electronic loads take their full charge from the connected battery and convert it into AC voltage with an efficiency of up to 96%. This is then fed back into the local power grid and reused, thus amortizing the purchase price via reduction of electricity costs.

3 – Economy through time savings

The time saved in discharging the energy storage units using high input powers of up to 15kW in 3U enclosures or 30kW in 4U enclosures increases cost-effectiveness. In addition, the devices can be combined to form high-performance switchgear cabinet systems with a total output of up to 1.92MW.

4 – High flexibility in use

Versatile and flexible: Due to true autoranging capability of the EA Elektro-Automatik device series, battery storage systems with different system voltages can be discharged with only one electronic load. For example, full power is available with one device for both a 400V and 800V system.