What is a solid state battery and how will it transform EVs, laptops, and phones in the future?

Mobile technology and the newest electric vehicles have much in common, despite what common sense might tell you. They are both operated by similar processors, and they are both a significant part of every owner’s life. However, they also share their biggest weakness – the battery.

It has to be said that batteries – especially rechargeable ones – have come a long way. Modern lithium-ion batteries offer high capacities and can be recharged many more times than even a few years ago.

Related: Can you overcharge your phone? Tips for how to extend your phones battery life

However, with the growing EV market, as well as the ever-increasing reliance on tech such as smartphones and wearables, which all need long-lasting batteries, the demand for better cells is at an all-time high. It also seems that lithium-ion cells can only get us so far. That’s why manufacturers are also trying out different technologies. One of the most promising ones seems to be solid-state batteries. Here’s everything you need to know about that type of battery.

Why are lithium-ion batteries not enough?

Lithium-ion batteries are in every piece of rechargeable tech nowadays. From the smartwatch on your wrist to your laptop to the electric car you drive, they are responsible for powering the newest tech.

However, they still have quite a lot of shortcomings that heavily impact the way we use technology. The two biggest flaws of lithium-ion batteries are undoubtedly their capacity and the fact that they are extremely fragile (and dangerous when damaged).

Smartphone batteries keep getting bigger, and their CPUs are more efficient. However, we still generally have to charge them every day, as there is a limited amount of power that such a small lithium-ion battery can hold. It might not be as annoying for a phone, but smartwatches and other wearables have to heavily sacrifice performance to reduce their power usage. If they could maintain their small form factor and get much bigger batteries, we could expect many more features to follow.

The same is true for electric cars – people want their EVs to be able to drive thousands of kilometers without needing a recharge. Still, the size of their batteries is limited both by the size of vehicles and by the massive weight of the cells themselves.

This means that lithium-ion batteries are often the cause of the limitations in tech that we complain about. This is also why manufacturers are looking for different ways of overcoming them – including betting on different battery technologies.

What is a solid-state battery?

One of the biggest technological hopes when it comes to extending the battery life of your mobile devices is solid-state batteries. The likes of Toyota and Samsung have championed these for use in their future electric cars and devices. Still, many more automotive and tech companies are now doing research on this technology, hoping that it will one day replace lithium-ion cells.

As the name suggests, solid-state batteries do not have any liquid inside of them. This is in contrast to lithium-ion batteries, which include a liquid electrolyte that allows lithium ions to flow from the anode to the cathode, transferring power stored in the battery to the device that is being powered. Solid-state batteries function similarly, but they exchange the liquid electrolyte layer in the battery into a solid electrolyte. This goes along with the changes to the anode; lithium-ion batteries are made with graphite that has lithium ions enclosed in it, and solid-state batteries opt for a solid lithium metal anode.

These two changes mean that the cells themselves are much smaller, as the electrolyte layer, as well as the solid lithium layer, can be significantly smaller than their counterparts in the lithium-ion battery. This is one of the reasons that solid-state batteries are so much more energy efficient than the older standard.

Why are solid-state batteries better?

Solid-state batteries, if all the hope related to this technology will come true, are set to be a game-changer. Here is a list of the main benefits of this tech compared to lithium-ion cells:

• They have higher capacity – solid-state batteries can store much more energy in the same volume. This allows devices using them to run for much longer while not being any bigger.
• They have higher energy density with lower weight and higher energy density – that is, they store more energy in the same volume as lithium-ion batteries. Solid-state batteries are also lighter than their lithium-ion counterparts. This makes the devices lighter while not losing out on battery capacity.
• They charge faster – solid-state batteries charge much faster than lithium-ion cells. It is expected that a solid-state battery in an EV should charge to full capacity in around 10 to 15 minutes.
• They can be charged and discharged more times – solid-state batteries are also more durable than lithium-ion batteries. Nowadays, lithium-ion cells usually guarantee 80 per cent of their original capacity after 1000 charge cycles. Solid-state cells should significantly improve on that score.
• They are safer – solid-state batteries are not as prone to damage as lithium-ion cells, as there is no dangerous liquid inside. Moreover, they also do not expand and cause explosions, as is the case with some improperly installed lithium-ion cells. Solid-state batteries are also less prone to mechanical damage, making them easier to use in various environments.

How will solid-state batteries transform EVs, laptops, and phones in the future?

As you can see, there are many (at least theoretical) benefits that solid-state batteries have over their lithium-ion counterparts. So, with these in mind, how could they change the tech industry?

Let’s start with EVs, as this industry has been pushing solid-state batteries the most. The hope is that by reducing the weight and increasing the capacity of batteries, the next generation of electric cars will finally be able to get rid of their users’ range anxiety.

Most users require their cars not only to be great in the city but also to allow them to go on a longer ride every once in a while without the need for refueling/recharging. With modern EVs, this is quite tricky, as their ranges max out around 300 miles/500 kilometers at best.

Solid-state batteries might be the answer, as in the same volume, they could provide much more power, resulting in much longer ranges. Moreover, as the batteries themselves are lighter, the reduced weight would also positively impact the range of future EVs.

However, this change is not only significant for cars. If solid-state batteries prove lightweight and energy-dense enough to power electric engines in flying machines, we could see an even bigger impact on the industry, as planes are now the only vehicles that have been unable to take advantage of the electrification boom.

However, vehicles are not the only tech that could be much better with solid-state batteries. These cells could also heavily impact your everyday electronics, such as laptops and phones, but most significantly, smaller wearables. As the batteries are more energy-dense and lighter, it could mean either smaller and lighter devices with similar battery life or, even better, devices with weight and dimensions similar to what we know now but that could last much longer on a single charge.

This change might not be as huge for everyone who charges their phones overnight, but it might prove invaluable to devices such as smartwatches. Take, for example, the Apple Watch 9. It’s a stellar device with one fatal flaw: its battery life. As the watch can only run around a day on a single charge, you always have to remember to charge it and find the time of day to do it. Solid-state batteries could eliminate that problem, along with making charging much faster.

Some products that solid-state batteries could benefit

Why are solid-state batteries not available yet?

Of course, for now, all these benefits are little more than wishful thinking. Even though solid-state battery technology is not just a theory – there are working prototypes – its commercial implementation is still far away.

The biggest hurdle that solid-state batteries have to overcome right now is the manufacturing cost. It’s true that solid-state batteries promise to be much better overall, but their costs right now make them not viable for consumers.

This cost is due to a much more complicated manufacturing process, as well as more pricey materials that are needed to create a solid-state battery. Moreover, it’s also the cause of the scale of lithium-ion batteries being manufactured – as they are produced commercially in huge quantities, manufacturing them is much cheaper than a still-niche product.

It also has to be said that all the benefits that solid-state batteries bring to the table still aren’t realized in the finished product. Even though the tech has the potential to deliver on all of these fronts, the manufacturing processes are still underdeveloped. It means that so far, not all the claims have been achieved, at least not all simultaneously.

There are also safety concerns. It’s true that, in general, solid-state batteries are safer than lithium-ion ones, as they have much fewer weaknesses. However, they come with issues of their own. The biggest one is their proneness to short circuits, which is caused microscopic growth of lithium metal called dendrites.

However, even with all these caveats, solid-state batteries are considered the batteries of the future. If their promises finally become a reality, we might expect a whole new era of electronics and a completely new way to use your everyday tech accessories.