Does fast charging affect battery life? Yes, but not at StoreDot

StoreDot, a pioneer of extremely fast battery charging (XFC) technology, has published a comparative analysis of how the degree of operability of batteries from various manufacturers changes over time.

 

Since July 2021, the shares of the Israeli startup StoreDot have been included in the portfolio of investors of Veligera Capital.

The comparison involved batteries used in electric vehicles Tesla, Mercedes, Porsche, Audi, Hyundai and Lucid. The SoH (State of Health) indicator was evaluated — a value reflecting the current state of the battery compared to its ideal state, literally — the state of health or the degree of operability.  The StoreDot battery, before its SoH level dropped to 80%, withstood more than 1250 continuous sequential cycles of extremely fast charging at a charging speed more than three times faster than most modern lithium-ion batteries. Even after 1700 cycles, which is much more than the generally accepted industry norm, StoreDot batteries retain 70% of their original capacity.

The results of the StoreDot “100in5” battery mean that:

Currently, a typical electric car with a nominal battery capacity of 60 kWh can add 100 miles in just under 17 minutes of fast charging from a powerful DC — this is largely dictated by modern lithium-ion battery technology, which limits the charging speed to about 2C (the charge and discharge rates of the battery are determined by the indicator C-rate, 2S =30 minutes). On the other hand, the StoreDot Extremely Fast Charging (XFC) battery is capable of charging up to 80% in 10 minutes, which reduces the charging time by 100 miles to 5 minutes. This does not affect the SoH and therefore the battery life.

 

To increase the battery life of an electric car, many manufacturers recommend drivers to use DC high-speed charging stations only when necessary, and to choose a home, slow AC charging for daily recharging. This may be good advice for extending battery life, however, residents of central urban areas who use public fast charging stations and do not have access to home chargers are unlikely to be able to use it.

 

The impact of fast charging on the condition of batteries is of interest not only to drivers. As manufacturers seek to extend battery warranties based on working condition for a certain mileage, it is extremely important for them to orient their batteries for the future when a more powerful charging infrastructure is deployed.

 

There are already 16 million electric vehicles in the world, of which 6.6 million were sold in 2021. This means that the development of charging systems and, in particular, battery packs capable of safe ultrafast charging without negatively affecting the service life or the level of degradation of the battery is becoming more and more urgent. The results of StoreDot’s work confirm that very soon owners of electric vehicles will no longer have to exchange the charging speed for the service life of expensive batteries.