An American company believes to have found a new battery concept that would allow cost reductions and better performance. Scientists from AMPAC and UCF seem to confirm the breakthrough. Another step in bringing EVs closer to real life use.

Batteries are the stumbling block in the development of electric vehicles and one major barrier to their commercial roll-out. Cost, technology, production, raw materials... batteries are difficult in many aspects.

Some promising concepts do exist. The German Evonik's lithium-ceramic battery seems suitable for mass-production and automotive applications. Its ceramic, yet flexible membrane separator technology can withstand more extreme heat when compared with traditional polymer membranes in common lithium ion batteries, making the lithium-ceramic battery safer and more reliable. Lithium-ceramic batteries furthermore offer high energy storage capacity.

The new approach

Planar Energy has tried something else. Instead of the typical liquid electrolytes, the young company (founded only in 2007) opts for a new new generation solid state electrolyte in large format lithium-ion electric vehicle batteries that would reduce costs (by up to 75%), save materials and assure (2 to 3 times) better performance and efficiency.

The technology was tested by the University of Central Florida's (UCF) Advanced Materials Processing and Analysis Center (AMPAC) which confirmed that this new generation of solid state electrolytes has ionic conductivity metrics comparable to liquid electrolytes used in traditional chemical batteries.

Planar Energy had started out with working on solutions-based materials deposition at the former Bell Labs research center in Orlando. This work was then continued in collaboration with researchers from UCF with focus on low-cost solar films and energy storage materials.

The company has published following test results on their solid electrolytes:

• A new class of solid state electrolytes was identified that have conductivity of 10-4 in measured samples and 10-3 in functional battery calculations. The conductivity ranges displayed allow for high-rate batteries required in automotive applications.
• The solid state electrolyte materials are deposited – stacked – as thin films directly on active layers in the battery, eliminating the historic process of having to deposit films on separate substrates and then mechanically joining them.
• The electrolytes demonstrate the same performance level of liquid electrolytes currently used by the lithium-ion industry, but they are in a solid form factor.
• The change in form factor greatly simplifies the battery manufacturing process and enables existing battery chemistries to function at 95% of their theoretical value.
• These batteries will be intrinsically safe, allowing customers to further reduce packaging requirements, as well as simplify the battery management system.
• These batteries have virtually no self discharge, allowing them to sit for long periods of time while retaining their charge. Traditional lithium-ion batteries have high discharge rates that are problematic for automotive applications.

Solid state battery fabrication could potentially enable manufacturers to increase their capacity by 200-300% while cutting costs by half at the same time, dismantling one of the barriers still in the way of electric vehicles mass roll-out.