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What is the purpose of this thing on NiMH rechargeable batteries? I can't figure out what this component is or what it is for.

I'm trying to change the batteries in a Hoover automated vacuum cleaner.

I want to know if it is necessary to have these on the new set of rechargeable NiMh batteries.

  • \$\begingroup\$ Are you asking what the connector is for? Because from the photo it just looks like a connector to me. But I have to assume you wouldn't be asking what a connector is for. \$\endgroup\$ – DKNguyen Feb 12 at 18:50
  • \$\begingroup\$ It appears to be a crimp connector. You put the wires in it and crimp it. \$\endgroup\$ – jwh20 Feb 12 at 18:59
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    \$\begingroup\$ The page in the background is nicely in focus. The blurry thing in the foreground could be a fuse. Draw the circuit. \$\endgroup\$ – Transistor Feb 12 at 19:11

It looks like a thermal protector. This is likely a self-resetting bimetal type, unlike the cylindrical type that has a low melting point metal inside with a spring- they open once and then have to be replaced.

Here is a typical product (photo from Alibaba):

enter image description here


Thermal protection.

A sane battery is expected to have one for fire safety.

May be either a fuse (single-use) or a bimetal disconnector (reversible - reconnects the circuit once cooled).

Most of these have a temperature written on them.


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