Lithium-ion battery technology, introduced more than 25 years ago, is reaching its limits. As a battery chemistry powering EVs, lithium isn’t expected to provide the energy density and extended range needed to satisfy government mandates for emission-free alternatives to gasoline- and diesel-powered vehicles.

This list of governments mandating the demise of internal combustion vehicles (ICEs) includes Norway (2025), Great Britain (2040), France (2040), India (2030), and China (no date given). For EVs to fully replace ICEs by these deadlines, higher-performing battery technology chemistries must be developed.

Current EV batteries are manufactured with expensive and flammable liquid electrolytes. Solid-state batteries, so named since they don’t contain the liquid electrolytes present in lithium-ion batteries, are instead composed of solid conductive materials that show promise for future use in automotive applications.

1. EMotion will have a top speed of 160 mph, according to Fisker. (Source Fisker Inc.)

Recently, Fisker Inc., which plans to introduce a sporty luxury EV called EMotion (Fig. 1), said it’s developing a solid-state battery with 2.5X the energy density of today’s lithium-ion batteries, as well as with high electronic and ionic conductivity (Fig. 2).

The new battery incorporates three-dimensional electrodes. It will deliver—hold onto to something sturdy—500-mile driving range and charging times as low as one minute. The company further claims the battery promises to be safer and lighter than the lithium-ion battery technology that powers today’s EVs. That’s not an outrageous claim, since solid-state battery tech replaces liquid acid electrolytes with solid materials and should be less prone to catching fire, short-circuiting, or degrading over time.

Solid-State’s Mercurial Journey

Fisker has been back and forth regarding its use of solid-state batteries. Initially, Fisker announced in 2016 that the EMotion would arrive with next-generation lithium-ion cell technology made by LG Chem, using graphene electrodes that would provide 400 miles plus range for the electric car.

2. Solid-state batteries hold the promise of offering roughly twice the energy density of lithium-ion and other “liquid” batteries per pound. (Source: Toyota)

Subsequently, in November of 2017, Fisker revealed patents for solid-state cell technology and announced a range of over 500 miles with charging times as quick as one minute. However, the company never disclosed whether the batteries would launch with the car in 2020. The latest prototype of EMotion, which purportedly will sprint from 0 to 60 mph in under three seconds, was revealed in January at the 2018 Consumer Electronics Show.

Now the story has taken yet another turn, and solid-state batteries are back on the table. In an interview with the E For Electric YouTube channel, Henrik Fisker, the Danish-born CEO and entrepreneur after whom the company is named, said that he now hopes to begin manufacturing the sporty luxury sedan with solid-state batteries right from the outset, even “if that means we have to delay the launch for some months.” Fisker said the company plans to start doing on-road tests with the battery next year.

Solid-State is Trending

Fisker isn’t alone in chasing “the holy grail” of battery chemistries. Toyota aims to commercialize solid-state batteries for electric cars by 2022. Japan’s NGK Spark Plug Co., based in Nagoya, Japan, has been trying to leverage its expertise in ceramics technology used in spark plugs to expand into all solid-state batteries.

In addition, Ionic Materials, Woburn, Mass., has come up with a polymer electrolyte that allows the use of high-energy materials and supports lithium-ion cells with low or even no cobalt in their cathodes. The solid polymer electrolyte material, Ionic Materials’ key invention, is said to conduct ions at room temperature rather than the 0°C (140°F) where most materials in solid-state research operate. The company also says the polymer is compatible with lithium- and alkaline-based batteries.

Earlier this year, Ionic Materials announced it had secured $65 million in a Series C financing round from a leading group of financial and strategic investors. It didn’t name the investors, but published reports not disavowed by the company said the investors included South Korea’s Samsung Group, the UK’s Dyson Inc., and Alliance Ventures, a venture capital fund jointly controlled by automakers Renault S.A., Nissan Motor Co. Ltd., and Mitsubishi Motors Corp.