Posted April 26th, 2022 in News

By Steve Farmer, Innovation Director at AMTE Power

AMTE Power has been making battery cells at its Thurso factory in Scotland for 30 years. We’re now leveraging this engineering heritage and expertise to drive forward our growth plans for the business.

Having our facility at Thurso gives us a number of advantages as a business. The obvious one is that we’re one of the only cell manufacturers working in the UK right now, with commercial partnerships in place to support requirements for energy storage and specialised automotive industries.

The game-changer for AMTE Power, however, is really that Thurso allows us to perfect the manufacturing process for our batteries as we look to deliver mass production volumes. Using our existing factory, we can anticipate what challenges or opportunities large-scale manufacturing rates might bring. This gives us greater certainty on both cost and the reliability of supply for our customers. This is also supported by the work we are doing with the UK Battery Industrialisation Centre in Coventry.

One of the most important parts of the manufacturing process to get right is the end of line testing for new cells before they are sent to customers. It accounts for one-third of all production costs. If this stage can be shortened, however, significant savings can be passed on to customers. It also means the footprint of new factories can be reduced because less space is needed for storing cells while testing is ongoing. If you think about the impact of these factors as we head towards larger production rates – from 0.5 GWh, up to 10 GWh – you get a feel for how important this is.

Fine-tuning the process

End of line testing can take up to three weeks, but the ideal time for different cell chemistries is unknown. State-of-the-art technology is needed to work this out and we’re now collaborating with partners at our Thurso site to do exactly that for our Ultra High Power cell.

Specifically, this project focuses on the ageing process for new batteries. The ageing process is related to optimising the contact layers (interphases) between the anode, cathode and electrolyte. These interphases are crucial for a good state of health at the beginning of a cell’s life, helping to protect and guarantee its long-term performance as well as safety. That’s particularly important for batteries used in cars or energy storage systems because they need to be reliable over an extended period of use.

Small changes, big savings

During the ageing process, a very small current flows through a cell. This decreases as the process gets closer to being finished, so by tracking how it changes we know when this stage is complete and exactly how much time to allow for it in future. Because the current is so small, it’s difficult to measure accurately using conventional methods so we’re developing an imaging system which uses quantum sensors. These detect the strength of the magnetic signal created by the current flowing through the cell.

It’s a complex process but this precision engineering will ultimately help us deliver high-performance for our customers and drive efficiencies as we grow our production rates. And by doing it now, it means we can stay ahead of the competition.