View single post by Robert
 Posted: Sun May 6th, 2018 03:15
Robert



Joined: Mon Apr 2nd, 2012
Location: South Lakeland, UK
Posts: 4066
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 The development won't be earth shattering, guessing five % improvement maybe? One of the things that has happened is the plastic bag or pouch the chemicals are wrapped in has been made thinner and is more effective at isolating the layers, I understand the inside of these batteries are a bit like a swiss roll, with a thin, sealed pouch of plastic containing the active chemicals is rolled up inside.

The leak-down over time is caused by some chemical reaction across the layers causing the battery to loose charge on the shelf. More modern technology has improved the charge shelf life and slightly increased the charge capacity. Newer cells are more efficient due to improved technology, they still have the same basic chemistry.

This is why leakage of rechargeable batteries is dangerous, if the plastic pouch ruptures then the chemicals can react and catch fire. Overheating is one risk, that's why soldering tags directly to the cels is a big no-no, they have to be spot welded, where the heat while hotter it is much more localised and safer when done in the factory or with properly regulated welders.

Panasonic, Fujitsu and Eneloop batteries are a big improvement compared with previous generations of rechargeable batteries, but EXPENSIVE.



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Robert.