UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - NiCad Battery

G6Tanuki · 17th Jan 2022, 5:30 pm

The "thing" in series with your cells is, I suspect, a "Polyfuse" - if the battery-pack is shorted then the Polyfuse heats up and turns into a very high resistance; remove the short, let things cool down and the Polyfuse goes back to near-zero-Ohms.

A good way to both protect the battery-pack against shorts, and also save the drill-motor from burning-out due to excess durrent if it is stalled.

17th Jan 2022, 5:30 pm	#4
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,998	Re: NiCad Battery - Internal Component ID The "thing" in series with your cells is, I suspect, a "Polyfuse" - if the battery-pack is shorted then the Polyfuse heats up and turns into a very high resistance; remove the short, let things cool down and the Polyfuse goes back to near-zero-Ohms. A good way to both protect the battery-pack against shorts, and also save the drill-motor from burning-out due to excess durrent if it is stalled. __________________ I'm the Operator of my Pocket Calculator. -Kraftwerk.