EV-battery to last for 3,5 million kilometers?
Jeff Dahn, head of the Canadian Battery Research Institute, has presented new results of his team’s work to ‘upgrade’ battery cells with additives making them last for 10 000 charging cycles. That would give a medium-range electric car’s battery a theoretical lifespan of over two million miles or 3,5 million kilometers.
Dahn and his researchers have a five-year partnership with Tesla until mid-2021 for the development of new long-lasting battery cells. Last year in September Dahn published a paper predicting his battery cells to last one million miles or 1,6 million kilometers. But in a lecture published on YouTube Dahn now goes a lot further.
Up to 15 000 charging cycles
According to Electrek, the scientist recognized as one of the Li-Ion battery pioneers, referred to new test results of his battery cell chemistry, exceeding for some of the cells 10 000 charging cycles. That is after three years of testing with one-hour discharge and one-hour charge and testing results every 100 cycles.
In a medium-range car capable of driving 350 km on a fully charged battery pack, this 10 000 cycles would mean 3,5 million kilometers. But Dahn also showed results claiming that based on different depths of discharge, with batteries charged regularly before being exhausted – 15 000 cycles are possible.
As electric cars are used for relatively short average distances a day like 45 km, according to Electrek, they would “show very little to no capacity degradation when they are discharged between 25% to 50% of their capacity. Which is actually how most people use their cars.”
More than 40 patents
The new generation batteries Tesla is working on with CATL are said to use chemical additives to store more energy for more extended periods. The development is done in collaboration with Dahn’s team of Canadian academic battery experts. Tesla decided to finance in 2016 the research group at the Dalhousie University in Halifax, Nova Scotia.
The partnership is for five years until mid-2021, and Tesla has since filed at least six patent applications that mention the Canadians as co-inventors. Dahn himself is listed as co-inventor of more than 40 battery patents since 1988. Eight of his former students are working for Tesla today.