Fast Charging Using Integrated Battery Thermal Management
This past November, PSD made the pilgrimage to the “Motor City,” The Automotive Capital of the World…on our computers.
The Battery Show and Electric & Hybrid Vehicle Technology Expo (rebranded as The Battery Show & EV Tech Digital Days) has a proud history of spotlighting the latest in automotive and battery innovations, and while 2020’s event (the in-person version) became yet another COVID cancellation, we did catch a (virtual) glimpse at some really cool technologies.
One of those recurring technologies was quick-charging which, as I argued in a previous editorial, is vital for the Internet of Things and solving the “range anxiety” associated with electric and hybrid vehicles.
AllCell Technologies discussed a new twist on this concept with their presentation "Fast Charge of Lithium-ion Batteries Using Integrated Battery Thermal Management (iBTM)."
Countless vendors are rolling out quick-charge solutions, but as we’ve learned from several, high-profile EV fires, thermal management is critical for the health of the batteries and the expected deluge of electric vehicles over the next decade (up to 31.1 million in sales by 2030, according to one source).
As Said Al-Hallaj, Co-Founder & Senior Technical Advisor at AllCell Technologies LLC, pointed out in his seminar, "Growing demand for battery electric vehicles has accelerated the need for advanced charging technologies to improve speed and reliability of the charging process. Lithium-ion technologies' high power and energy density, commercial maturity, constant technology improvement, and reducing cost makes it an attractive technology for such applications. Li-ion batteries, however, suffer from major safety risks and rapid aging….”
The ideal temperature of batteries is roundabout the body’s preferred temperature – 15-35°C – and thermal management improves battery life, reliability, and efficiency.
Indeed, active thermal systems can increase battery efficiency by up to 20%.
But it’s not that simple – Said notes that all Li-ion batteries (including LFP) have liquid electrolyte and are at risk of thermal runaway (Cell Thermal Runaway (TR) defined as uncontrollable heating > 10 degrees c/min).
And current quick-charge solutions can lead to mechanical degradation (lithium metal forms dendrites, leading to poor battery performance, amongst other risk factors).
AllCell’s Integrated Battery Thermal Management solution was already tested with a commercial drone battery, with the next logical step being EV and hybrid batteries, and they noted that, in the future, they want to work on fast charging in cold conditions.
Of course, this is barely scratching the surface, as AllCell’s seminar was more of an introduction. For more information on their iBTM and their full suite of battery and thermal management solutions, check out their site here.
