Each new generation of EVs works to address consumers’ concerns of extending vehicle range and recharging time. This need is driving advances in Li-Ion battery technology and alternative technologies like solid-state, zinc-air, graphene batteries, and many others.
Regardless of the technology, EV battery systems must undergo rigorous testing for operating voltage level, charging rate, rating, and use case, both while under development and in the battery manufacturing process. They also are tested during the EV manufacturers’ production testing.
A typical battery cycling and test system in use today employs a rack of programmable power supplies and loads (“Cycler”) and another rack with an industrial PC, test equipment, and communications systems. The battery packs are cycled while operating at a controlled temperature prescribed by the specific test protocol. Depending on the type of power supplies employed, a cycling test may require interruption to allow the instrument to change range as the battery pack voltage ramps up or down.
An alternative is to use an adaptable cycling and test system that is much lighter on its feet and can easily adjust to whatever changes are required in the fast-changing battery technology environment.
Key elements of an adaptable battery testing and cycling system include:
• Bi-directional, Regenerative, Auto-ranging Power Sources
• Adaptable Testing Software
• Integrated Power Control and Measurement
Bi-directional, regenerative supplies essentially “borrow” the utility power by using an internal synchronous inverter to return most of the power used in the test back to the grid.
Auto-ranging adds flexibility to the entire system. Compared with “conventional” power supplies that provide maximum power only at the rated voltage and current, auto-ranging allows for maximum power to be delivered over a wide range of conditions. For example, a conventional test system configured for 400V battery packs would require the replacement of the power supplies to be reconfigured for 800V batteries. With auto-ranging, the maximum power output would be delivered without any reconfiguration.
The EA-BCTS 10300 system includes adaptable testing and cycling software offering a full range of pre-programmed test protocols and simple means for implementing user-defined tests such as capacity, four seasons, pulse, and imported battery cycling. Built-in drive cycle simulations include FUDS, SFUDS, GSFUDS, DST, and ECE-ICL.
It also integrates “Power Control and Measurement” in the form of an operational interface between the battery packs being cycled and tested and the programmable bi-directional power supplies.