Soldering up a DFRobot Battery Protection Module FIT0869

My question is about the physical characteristics of this board. It has six connection points on it.

P+ and P- are straightforward - they’re solder pads with holes in them where you can stick a wire.

The other four connectors are weird. They’ve got slabs of metal soldered on top of them. I didn’t realise this until i tried to solder a wire on and the slab started slipping away.

So my question is, why? What’s the point of the slab of metal? It’s not physically mounted with any method other than solder. It just sits in the way of the pre drilled hole.

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I think you’d better ask this question in DFRobot’s forum.

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Hey Aaron,

The reason that the 18650 Battery Protection Module has the metal pads soldered to the board, is that the 18650 battery is meant to be spot welded to these pads, not soldered. If these pads were not present and someone tried to spot weld the battery tab to the board it would most likely blow a hole straight through.

Within a multi-cell 18605 battery pack, all of the batteries are spot welded together in series. This unit follows the same idea, as it’s common thinking that soldering and/or putting too much heat into a 18650 is generally a really bad idea.

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Okay, that makes some sense.
I just noticed the pads are about 18mm apart, same as the battery diameter.

I don’t see how you’d wire it direct to cells though.
I’ve been using product FIT0539 instead, with some extra fat wires installed between cells. Seems to work.

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Thanks for the broad answer.

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