Battery giants ready for battle over patent

摘要

The imminent launch of batteries with built-in charge testers has sparked a major patents row that will embarrass the US patent office and bring market leaders Duracell and Ever Ready into legal conflict. Duracell and Ever Ready each announced recently that they are to put tester strips On all their batteries. Both testers work on the same principle. If the battery is still fresh, when the user presses a pair of pimple switches on the battery casing, current flows through a resistive strip, heating it up and changing the colour of a thermochromic chemical. Duracell's version looks like a thermometer, while Ever Ready's Energiser tester displays the word "good" if the battery is still producing a strong current.