Continuous battery monitoring for electric and plug-in hybrid vehicles

Continuous battery monitoring for electric and plug-in hybrid vehicles is essential, especially for operators of large fleets. Fleet managers can then be confident that every vehicle is ready to use. Monitoring is equally important in extending the service life of batteries in electric vehicles and plug-in hybrids. Monitoring enables targeted measures to be taken to reduce the total cost of ownership (TCO). We are therefore working with partners to develop an innovative and efficient solution using "digital twins".

In electric vehicles, the battery is by far the most expensive component. It is, however, difficult to estimate the condition and remaining service life of this core component due to aging behavior being dependent on how a battery is used and charged. Battery aging becomes evident from a lower range, loss of performance and longer charging times. To test remaining capacity – i.e. a battery's current "state of health" – we provide a quick check. More advantageous, however, would be to monitor the full life cycle and charging history of an electric vehicle's battery in everyday operation and to optimize service life through specific measures such as smart charging management.

This concept has been developed by Twaice, a start-up that we support. The idea: an electric vehicle transmits all battery data as well as number, type, and length of all charging processes to the cloud where a digital image of the battery "ages" in step with the real battery.

Continuous monitoring and state-of-the-art simulation programs then enable the system to predict how battery capacity will diminish over a specific period according to charging behavior and usage profiles. From these models, recommendations on driving behavior and charging management can be formulated which will help to prolong battery life.

Example: If the battery of an electric vehicle (BEV) or plug-in hybrid (PHEV) in one vehicle in a fleet has been subjected to stress from long trips and multiple quick charging, but another vehicle has been subjected to short trips and low charging currents, managers can swap routes at the appropriate time. By the end of the planned period of use, both vehicles will then have fulfilled their tasks without the need for expensive battery replacement. The digital twin can also provide information for predictive maintenance, i.e. optimum maintenance and repair intervals.

For electric buses in public transport, a digital twin also enables managers to know exactly when to deploy vehicles on alternative routes. Local transport operators, who generally write off buses over a period of twelve years, can then achieve maximum usage and are able to plan with confidence.

For manufacturers, the digital twin provides great benefit, even before the battery or vehicle exists. For example, developers can use our simulations to estimate how installing a cooling system will impact on battery life. They might also be able to adjust the basic dimensions of an energy storage system. It's not unusual for batteries to be too large – and therefore too expensive – for their intended use. Information from the digital twin thus saves costs in development, procurement, and production.

Fully documented battery life also allows residual values of electric fleet vehicles to be accurately determined at the end of their service life. And last but not least, our experts can use the digital twin to estimate when it makes sense to use an electric car battery for second-life applications.

To learn more about digital twins and smart charging management our experts will be happy to advise and assist you – locally in your region!