Battery with integral condition tester
CA 2073901 C · Owner: Duracell Inc. · Inventors: Kiernan, Charles E.; Wang, Chih-Chung; Eisensmith, Terry C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to an electrochemical cell and an integrally related state of charge indicator. The state of charge indicator has two electrical contacts and a display means connected therebetween. A first contact is connected to a first cell terminal and a second contact is unconnected to either terminal. A switch means permits electrical connection of the second contact to the second terminal to visually indicate the condition of the battery by the display means.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed July 15, 1992 and granted January 4, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 15, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 15, 2014.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.