A brief summary of NiMH cells and their charging techniques, and why smart chargers are usually not so smart.

Nickel Metal Hydride cells are almost a legacy cell, in that they are designed to literally fill the gap of alkaline and zinc cells. In reality, lithium ion technologies are a much better option for future products. But where it's useful to be able to swap cells for instant power replenishment the NiMh cells have a safety advantage over lithium cells.

Things worthy of note in this video. Smart chargers may not recognise a fully discharged NiMH cell. If the cell is given a slight boost from another cell or slow (dumb) charger, the smart charger will recognise it again and charge it.

If a cell is old or has low capacity, a smart charger may end the charge cycle prematurely - sometimes within a minute. If that happens, check the cell has clean contacts and if that doesn't help then it can be charged to its absolute full capacity reliably in a traditional dumb charger that doesn't do any end of charge monitoring.

I almost forgot to mention the Rayovac IC3 charging technology. I think the product failed because it was sold as premium technology at a high price. It was the ultimate in precise and fast charging, allowing a 2000mAh cell to be charged in just 15 minutes with no risk of venting.
Other brands tried to compete using thermal charge end detection, but they were nowhere near the simplicity and reliability of the IC3 system.

If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.



#ElectronicsCreators