Solid gel membrane separator in rechargeable electrochemical cells
US6358651B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 11, 2000 |
| Grant date | Mar 19, 2002 |
| Priority date | — |
| Expiry date | Jan 11, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49108
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Rechargeable electrochemical cells that employ a highly conductive polymer-based solid gel membrane separator disposed between the anode and charging electrode are disclosed. The separator comprises a support or substrate and a polymeric gel composition having an ionic species contained in a solution phase thereof. In preparing the separator, the ionic species is added to a monomer solution prior to polymerization and remains embedded in the resulting polymer gel after polymerization. The ionic species behaves like a liquid electrolyte, while at the same time, the polymer-based solid gel membrane provides a smooth impenetrable surface that allows the exchange of ions for both discharging and charging of the cell. Advantageously, the separator reduces dendrite penetration and prevents the diffusion of reaction products such as metal oxide to remaining parts of the cell. Furthermore, the measured ionic conductivity of the separator is much higher than those of prior art solid electrolytes or electroyte-polymer films. The disclosed rechargeable electrochemical cells include, for example, metal/air, Zn/Ni, Zn/MnO2, Zn/AgO, Fe/Ni, and lead-acid systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.