3D printing enables robust and customisable structural lithium-ion batteries

Researchers at Shanghai University have developed a new method for manufacturing high-performance structural batteries using 3D printing. These batteries can be used both as energy storage devices and as load-bearing elements in vehicles. The results were recently published in the journal ‘Composites Science and Technology’.

The research team led by Yinhua Bao focussed on developing an integrated system that combines high energy storage capacity with good load-bearing capacity. Previous approaches to structural energy storage often suffered from low energy density and weak electromechanical cycle stability.

The Shanghai scientists’ approach is based on a decoupled design. This involves combining a 3D-printed structural framework with energy storage components. The framework assumes the primary load-bearing function, thus minimising the load on the energy storage materials.

Bao explains: ‘By using 3D printing, we can create customisable structural frames that, in combination with energy storage materials, form components with an integrated energy storage and load-bearing function.’

The researchers optimised their design using finite element simulations. They also selected high-performance electrode materials and electrolytes to improve energy density and service life. A distributed arrangement of the battery cells prevents total failure in the event of localised damage.

In tests, a prototype of the structural battery showed promising properties. It withstood considerable tensile and bending stresses with a high energy density of 120 Wh/kg. After 500 cycles, the battery retained 92% of its capacity. Under tensile stress of 80 MPa, 98.7% of the capacity was retained, and 97% under bending stress of 96.3 MPa.

The 3D printing method enables flexible customisation of the battery geometry for various applications. In addition to electric vehicles, autonomous robots or logistics vehicles could also benefit from the technology.

In the future, the team plans to further improve reliability by using new materials for the structural frames. Further research will also focus on applications in unmanned aerial vehicles and robots.