Self-Pressure Silicon–Carbon Anodes for Low-External-Pressure Solid-State Li-Ion Batteries

Although a high stack pressure (≥50 MPa) enhances solid-solid contacts in solid-state batteries (SSBs), it poses impracticality for commercialization. This work proposes a self-pressure silicon (Si)-carbon composite anode that enables stable operation under reduced external pressure (≤2 MPa). The self-pressure anode features a prestress structure that can effectively alleviate the internal and external stress simultaneously, which is fabricated with ionic-conductive poly(ethylene oxide) (PEO)/lithium salt-coated carbon nanotubes (CNTs) being compressed by shrinking graphene hydrogel. The capillary-driven hydrogel shrinkage generates internal pressure, compensating for the volumetric expansion (up to 300%) of…

• NN
  National Natural Science Foundation of China

  Awards: 52172040, 52402303, U23B2077, 52202041
• TS
  Taishan Scholar Project of Shandong Province

  Awards: ts202208832, tsqnz20221118, tsqn202211086
• NK
  National Key Research and Development Program of China

  Awards: 2022YFE0127400, 2021YFF0500600
• FR
  Fundamental Research Funds for the Central Universities

  Award: 23CX06055A