Manufacturing method for a current collector for anode-free all-solid-state batteries, a current collector manufactured thereby, and an anode-free all-solid-state battery comprising the same

Anode-free all-solid-state current collector inducing uniform lithium electrodeposition via a porous copper-tin nanotube layer

This technology creates a porous copper-tin (Cu3Sn) nanotube layer by forming copper hydroxide nanotubes on a copper current collector surface, followed by tin coating and heat treatment. This reduces overpotential during lithium electrodeposition and suppresses dendrite growth.

In anode-free all-solid-state batteries, high lithium electrodeposition overpotential leads to non-uniform lithium plating. This creates technical limitations, such as lithium dendrite growth and short circuits.

This technology involves treating a copper current collector with an alkaline hydroxide and persulfate solution to grow copper hydroxide nanotubes, followed by electroless tin plating and heat treatment to form an open-ended porous Cu3Sn nanotube layer. The expanded surface area maximizes contact with the solid electrolyte and ensures uniform lithium deposition. Applicable to anode-free all-solid-state batteries and high-density pouch cell current collectors, it maximizes volumetric energy density by eliminating the anode active material, achieving a capacity retention rate exceeding 83% after 150 cycles.

‍

‍

Key Features:

• Forming a copper hydroxide nanotube layer by contacting one side of a copper current collector with a solution containing alkali metal hydroxide, persulfates, and water
• Coating the surface of the copper hydroxide nanotube layer with tin using a tin precursor solution containing a tin salt, a reducing agent, and a complexing agent
• Heat-treating the tin-coated copper hydroxide nanotube layer to form a copper-tin nanotube layer consisting of open-ended nanotubes
• A copper-tin nanotube layer that reacts with lithium during charging to form a mixture of copper-tin, lithium-tin, and copper phases

‍

This invention was developed with support from the Ministry of Trade, Industry and Energy for the development of composite materials and electrode component manufacturing technology for 7 mAh/cm²-class high-energy-density electrode plates for ceramic secondary batteries.

‍