puck.js battery holder improvement

I purchased a few puck.js (all of them are hardware version 2.1a) and all of them seem to have a problem with the "newer" CR2032 battery, that are a little bit thicker, due to the surface on the back.
I had to resolder the battery holder, and put a little bit more solder on the surface but obviously that is not the best solution (and I am not nearly as good in soldering as the machines in the factory are).

I definitly affects other products as well (see https://www.youtube.com/watch?v=zz1POx0fw2w
), and I ask myself, if there is a better way to make the battery holder more robust. Maybe it is possible to change the holder with a other version like https://cdn-reichelt.de/bilder/web/artikel_ws/D600/BH1060.jpg ?

Hope to hear from you guys, if you have similiar problems.

BTW: Thank you @Gordon for all the great work you are doing. If you will ever be in Berlin/Germany, you will be my guest in every possible way :P

All the best,
David

Hi David,

Thanks! Sorry to hear about the battery holder issues - so just to be sure I understand what the issue is, you're saying that:

• the battery clip itself is fine - it's not come detached from the board at all
  
• It's the shape of the '-' terminal of the battery that doesn't reliably make contact with the gold area under the battery clip itself?
  
  

If so, this is pretty much the first I've heard of the problem - with prototypes we did have some issues like this, but I'd raised the size of the gold-plated area significantly and that basically fixed it for us.

I guess in future boards I might be able to enlarge that area still further (in some places) to avoid it. Do you have any links/pictures of this 'newer' CR2032 battery? I can't say I've really ever come across any differences.

I had wondered about a different battery holder, but it's a tricky one - pretty much everything is substantially thicker than the standard clip-style, and that would then require a whole new case.

After seeing that video, I should add - nobody should ever put the battery backwards in anything as he suggests right at the start. Puck.js does have some very basic reverse voltage protection (it shorts the battery out with a diode) but that's really a last resort protection and shouldn't be relied on (it'll also flatten your battery in minutes).

the battery clip itself is fine

The holder did come off the board in two cases after putting the battery in.
So basically the pressure (on the solder points) was so high, that it came off.
I learned from that and resolderd the other 2 Pucks before putting in the battery.
So it definitly IS a problem with the holder or the "new" kind of batteries (used VARTA CR2032 2pc Lithium Blister / EAN: 4008496746460).

The video is misleading in the way, that there is a contact problem, but he mentions, that his batteries are thicker too.
I do NOT have a caliper to measure the batteries and inside e.g. an Apple Airtag they seem to be perfect (also due to the different holding mechanism).

Since the name is "2032" one can think that it is 20 mm x 3.2 mm but as always some people like to break the rules ;)

Wow, I'm really sorry to hear that. I know it was an issue on especially the first batch of v2 Puck.js, but I thought we'd got that sorted now. When/where did you buy the Pucks? We do check them all with a little pressure on the holder before sending them out, but obviously not to the level of force that these batteries are putting on it.

Do the batteries you found really just not fit in at all, or it's more that they raise the pressure on the holder to the point where the solder fails? As you say, the '32' in 2032 really should be the thickness, so you'd hope that they would all be the same.

It's a shame you can't measure the offending Varta cells - if you put them side by side with another style, you can actually see a difference in height?