Are Solid-State the EV Batteries of the Future?
Lithium Ion (Li-Ion) has been — and still is — the leading technology for electric vehicle (EV) batteries due to their high energy density, affordability, reliability, and safety. But various challenges of Li-Ion batteries like limited charging times and energy density, degradation or potential environmental impacts foster the development or new technologies by engineers worldwide.
One of these alternative technologies could be solid-state batteries with the potential to offer even higher energy densities and faster charging times once the manufacturing challenges are overcome. However, there are still several challenges that need to be overcome before solid-state EV batteries can become mainstream. In this article, we'll explore the current state of solid-state EV batteries, the challenges they face, and how innovative foam and tape solutions can help solve them.
The name “solid state” is based on the electrolytes used to transfer ions between cathode and anode because they are: solid. These electrolytes are typically based on ceramics, glasses, or polymers. Due to their high ionic conductivity, it is possible to transfer ions without the need for a liquid or gel electrolyte like for example in Li-Ion batteries.
These solid electrolytes are typically thinner than liquids or gels electrolyte which allows for a more compact and thinner battery design. Therefore, the difference between solid state and Li-Ion technology can often be seen at first sight when the two different types are compared.
Now that we looked at general technological differences, let us have a closer look at why solid-state technology can be an interesting alternative.
Energy density and more lightweight, compact and powerful battery designs are key factors engineers are trying to improve. Here, solid-state technology with potentially higher energy densities in thinner designs can be beneficial for certain applications where space is limited.
Also, solid electrolytes can operate at higher voltages for faster charging times and longer lifespan. The materials used in solid-state electrolytes are less flammable and can help to improve safety by reducing the risks of thermal runaway and battery fires.
Although this sounds like an ideal solution — more power in the same or less space, faster charging and improved safety — this and other technologies are still in the development and testing phase. It will take time before they might be widely commercialized as true alternatives. In the following paragraph, let us see which main challenges currently limit a solid-state technology breakthrough and commercialization.
With today’s technologies, solid-state batteries are more challenging to manufacture compared to other designs. This increased complexity in manufacturing requires different equipment and know-how than traditional battery technologies which can be a cost driver. New and improved manufacturing processes for solid-state batteries will be needed before the technology can advance to a price competitive alternative. Today, there are a few companies who are working hard to find a way to scale solid-state battery manufacturing at a market price. They usually collaborate with a large OEM automotive sponsor that interestingly invests in more than one solid-state technology.
Due to their high energy density, solid-state battery designs also struggle with thermal stress even though the materials used provide higher thermal stability compared to other technologies. Innovative foam solutions can help mitigate risks and improve safety and performance.
Another challenge of solid-state EV battery design is mechanical stress or even cracking during operation or assembly due to their higher rigidity compared to traditional designs. Innovative adhesive tapes can not only streamline the complex manufacturing process, they can also help to mechanically stabilize the battery cells and distribute stress evenly across the battery pack. As process aids, adhesive tapes can significantly reduce the risk of cracking or damage during assembly or operation for improved output, quality and manufacturing cost reduction.
The EV battery technology landscape is varied and fast changing with all the ups and downs different solutions provide. There is no ideal or one-for-all solution existing, but we learned that solid-state EV battery technology can be an interesting road towards the electrified mobility of the future. Let your tape experts know where you would like to go so they can help guide you on your way and support you to reach your final destinations faster.