Can Solid-state Batteries Replace Lithium-ion Batteries in EV?

Lithium-ion (Li-ion) batteries have become the fundamental power source for electric vehicles (EVs), and their demand skyrocketed with the surge in the EV market. However, since the very beginning, some challenges raised doubts about the suitability of the technology in the long term.

Solid-state batteries with their solid electrolyte, are expected to provide greater safety and performance in comparison to lithium-ion batteries. The risks associated with lithium-ion batteries in an EV include High flammability, risk of leaking fluid, and Electrolytic decomposition at high voltages, all of which can be addressed by solid-state batteries. Now the question is, can solid-state batteries replace lithium-ion batteries?

Big Challenges to Lithium-ion Batteries

One of the major issues that critics of EVs point out is that Lithium-ion batteries in EVs catch fire. Batteries are the EV components susceptible to catching fires. While other challenges to lithium-ion batteries as a source of EV power, such as range anxiety and charging times, have been largely taken care of with technological advancements, other issues persist. EV fires, environmental impact, and rising lithium costs are among the major challenges to Lithium-ion batteries. Here’s How?

EV Fires – A Big Challenge

Lithium-ion batteries are losing popularity due to EV fire incidents. Li-ion batteries catch fire as they are extremely sensitive to high temperatures and highly flammable on the inside. Subject to external pressure, there’s a risk of the battery becoming very hot and exploding from overpressure. Further, the battery also overheats when the current surges. Furthermore, Lithium-ion cells also undergo self-discharge, which can cause temperatures to rise, leading to a Thermal Runaway also known as ‘venting with flames’.

There are enough stories to prove this point. Several fire incidences, including those of the likes of Tesla cars and Ford electric pickup trucks, make the news now and then. For instance, spontaneous battery combustion recently caused a car to catch fire in California, needing almost 6,000 gallons of water to put the fire out. In another incident, Ford Motor Co. suspended production and halted shipments of its F-150 Lightning electric pickup after a battery caught fire during a test drive in Michigan.

The increasing number of fire incidents is raising questions about the safety of lithium-ion batteries for EVs. As per media reports, as many as 22 lithium-ion battery fires happened in the first two months of 2023 in New York alone.

Environmental Impact- A Cause of Concern

Apart from all the visible issues with lithium-ion batteries, battery waste has the potential to pose a considerable environmental challenge in the future. The lithium-ion battery is indeed a facilitator of green and renewable power, however, battery end-of-life disposal remains a question mark.

Lithium batteries contain potentially toxic nickel, copper, and lead materials. When disposed of improperly, used batteries can lead to an environmental disaster, and if stored uncontrolled, they become explosive.

Rising Cost

High costs remain the major issue, as lithium prices are burgeoning owing to the surge of EVs. The global demand for lithium, also known as white gold, is predicted to rise further – to over 40 times by 2040, driven predominantly by the shift to electric vehicles. The primary problem is that the materials used in the manufacture of these modern batteries are rare earth minerals. The massive amount of Li-ion battery production needs to be fed by a select few mines across the world. As expected, prices of these minerals, especially that of lithium are bound to increase as mining costs increase.

The Solid State Battery

All-solid-state batteries (ASSBs) are expected to be a game-changing technology for accelerating the popularity of EVs. Apart from being much safer, solid-state batteries have the potential for energy densities approximately twice that of conventional lithium-ion batteries, significantly shorter charging time due to superior charge/discharge performance, and lower cost realised by using less expensive materials. These kinds of batteries are a rapidly developing and emerging tech touted by many as the next generation in battery technology.

There are enough grounds for many to believe that solid-state batteries may be able to knock lithium-ion batteries from their current market dominance.

Safer Technology

The most important ground is safety. The inherent flammability of the electrolyte liquid in a li-ion battery creates a ticking time bomb that can, and has, caused these kinds of batteries to spontaneously combust. This is where solid-state batteries offer far greater safety than their lithium-ion battery alternatives. The use of things like ceramic electrolyte alternatives is, for example, far less likely to combust. Ceramic materials also allow solid-state batteries to operate at far higher currents than equivalent lithium-ion batteries.

More Environmental Friendly

Solid-state batteries are not only safer alternatives but also reduce the carbon footprint of an electric car battery. A recent study commissioned by Transport & Environment from Minviro, Solid State Batteries can reduce the climate impact of batteries by 39 per cent compared to Lithium-ion batteries.

Unlike Lithium-ion counterparts, solid-state batteries use more common, and less toxic, constituents elements such as sodium.

Higher Energy Density

Over the past decade, several prominent automakers, including BMW, VW, Hyundai, and Nissan, have made multi-million dollar investments in the research and development of Solid-State Batteries (SSBs). These automakers are driven by the significant advantages that SSBs offer over current Li-Ion technology.

Solid-state State Batteries boast a notably higher energy density than traditional Lithium batteries, enabling automakers to store more energy per kilogram. This allows for a reduction in size and weight or enables the battery to provide a much higher energy capacity and deliver an exponentially greater driving range than a similarly sized Lithium-Ion battery.

Lithium-ion batteries also require external cooling which can take up precious space and energy. On the other hand, solid-state batteries result in a higher cell-to-pack ratio, lighter vehicles, higher energy, and power density, extended range, and fast charging.

Can Solid State Batteries Replace Lithium-ion Technology?

It is too early to make a clear prediction, yet the sentiment is positive for solid-state batteries. While solid-state batteries have their own set of merits, the technology is still too new. However, the promising technology has already attracted many proponents who are funding R&D toward the commercial viability of the technology.

So far, Japanese companies have dominated the race to develop the next-generation power source for electric vehicles. Toyota Motor is the leading holder of solid-state battery patents. Presumably, Toyota’s first SSB-powered EVs will start rolling out by 2025.

NASA researchers are also making progress and have already generated substantial interest from the government, industry, and academia, in an activity called the Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS). Their research seeks to improve battery technology by investigating the use of solid-state batteries for aviation applications. The US researchers at the Illinois Institute of Technology (IIT) and the US Department of Energy’s Argonne National Laboratory have also developed a lithium-air battery with solid electrolyte whose energy density could potentially be increased fourfold compared to today’s lithium-ion batteries.

Talking about solid-state batteries replacing lithium-ion batteries, QuantumScape released its performance data in December 2022 which revealed that their SSBs have a staggering Volumetric energy density of more than 1,000 Wh/L while the best batteries used in existing EVs go only as high as 700 Wh/L. The revelation turned heads and the auto-major Volkswagen responded with a five per cent stake in Quantumscape and its SSB technology.

Other proponents include the likes of Nissan and BMW. On a scale of probability, the merits of solid-state batteries make them more likely to replace conventional lithium-ion batteries as a prominent source of power in an electric vehicle.