Electric vehicle batteries typically require a tradeoff between safety and energy density. If the battery has high energy and power density — required for uphill driving or merging on the freeway — then there is a chance the battery can catch fire or explode in the wrong conditions. But materials that have low energy/power density, and therefore high safety, tend to have poor performance. There is no material that satisfies both.
Researchers have created a highly stable battery with highly stable materials, to which they introduced instant heating. Self-heating batteries overcome the problem of poor performance in cold climates. The battery uses an electric current to heat up in seconds compared to the hours an external heater requires. By heating the battery from room temperature to around 140 °F (60 °C), the battery gets an instant boost in reactivity, which increases exponentially with temperature.
The self-heating battery, called the All Climate battery, has been adopted by several car companies, including BMW. Because the batteries are built using stable materials, they have a long cycle life — even at 140 °F, their cycle number is over 4,000, which translates to over a million miles. Further work will be to develop a solid-state battery that will likely require heating as well.