In aerospace, defence and motorsport, battery weight can influence range, endurance, payload and overall system performance. At the Avocet Research Centre, this challenge led to the development of Flyweight, a bimetallic pouch cell tab designed to reduce the amount of copper traditionally required in an anode tab.
By combining copper and aluminium in a direct metal bond, Flyweight provides a lighter alternative while retaining copper where it is needed at the cell connection.
Why Battery Tab Weight Matters
A single tab contributes only a small amount to the total mass of a battery system. Across hundreds or thousands of pouch cells, however, those savings can become more significant.
This is particularly relevant in applications where every gram matters.
For aerospace and eVTOL platforms, lower battery mass can contribute to improved range or payload capacity. In defence applications such as unmanned systems, reducing weight can support longer endurance. In motorsport, controlling mass remains an important part of battery and vehicle design.
How Avocet Research Centre Developed Flyweight
Traditional anode tabs are commonly manufactured from copper because of its conductivity and compatibility with the copper current collector. Copper, however, is considerably heavier than aluminium. Flyweight uses copper at the cell side and aluminium through the remainder of the tab. This maintains a copper-to-copper connection at the foil stack while enabling an aluminium-to-aluminium connection at module level. Through materials research, prototyping and process development, the Avocet Research Centre helped turn this concept into a component suitable for practical battery applications. Flyweight is now manufactured in the UK by Avocet Battery Materials.
Supporting Weight-Sensitive Applications
For aerospace and eVTOL developers, reducing copper within each tab provides another opportunity to lower pack mass without changing the fundamental cell architecture.
In defence, lightweight battery components can help support applications where endurance and payload flexibility are important, including unmanned and portable systems. Motorsport presents similar demands, combining high power requirements with a continual focus on reducing weight. Flyweight can also provide greater flexibility in how cells are connected at module level.
From Research to Manufacture
Flyweight demonstrates how ARC can take an engineering challenge from initial materials research through prototyping, testing and process development towards manufacture. For battery developers in aerospace, defence and motorsport, reducing weight does not always require a major redesign. Sometimes, the opportunity starts with the tab.
