Title: POLYURETHANE BASED MEMBRANES AND/OR SEPARATORS FOR ELECTROCHEMICAL CELLS

 Number/Link: WO2013/062990

Applicant/Assignee: Lubrizol

Publication date: 2/05/2013

“Gist”:  TPU prepared from a DEG-adipate polyester diol, HQEE and 4,4′-MDI can be used as Li ion-conducting electrolytes  in electrochemical cells.

Why it is interesting: Because of the rapidly increasing use of phones, tablets, electric cars etc. research into improved batteries is a very hot topic. Many modern batteries use Li+-conducting seperators or ‘membranes’ with specific conductivity, solvent swelling and heat-resistance properties.  According to this invention  improved separator membranes can be produced from (a surprisingly simple) thermoplastic polyurethane based on (preferably) 4,4′-MDI, hydroquinone bis (hydroxyethyl)ether as chain extender and a DEG-adipic polyester diol with a MW of 2000 to 3000.  Lithium conductivity can (optionally) be further improved by incorporating Li+-conducting solids like Li-Borates, Li- silicates, Li salts or complexes and the like.

Schematic Li-polymer battery.