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by giantrobot 959 days ago
The case isn't so tight the batteries can't move. LiPoly batteries expand and contract when they heat and cool. The case needs enough space for that to happen without putting pressure on the battery.

When the battery is at its most contracted state it can move if it's not fixed to the case by some means. Movement of the battery puts stress on the connectors and can lead to a short (or worse).

Gluing the battery in the case is a safe way of fixing it in place inside the case. Screw tabs would give the opportunity during assembly of puncturing the battery casing with a tool or screw. They could also work themselves loose with the thermal expansion cycles.

But people like the thought-terminating "Apple bad" narratives.
2 comments
pineaux 959 days ago
Nah, this is just an apologetic just look at the amount of engineering they put in their Thunderbolt 4 cables: https://www.lumafield.com/article/usb-c-cable-charger-head-t...

Its crazy stuff. You are telling me they cant think of a secure way to use a mechanical, screwed system that is able to cope with the thermal expansion. I find that hard to believe. I believe it is mostly cost and profit incentive, MAYBE safety, but I also doubt that last one.

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bluescrn 959 days ago
Surely there's a non-adhesive material that'd serve that purpose though, some sort of foam or rubber perhaps?
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wtallis 959 days ago
I think adhesive and screws are the only two practical options for securing a battery well enough to prevent repeated cable flexing, which is probably much more of a concern than screws coming loose.
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kilburn 959 days ago
Are you saying these were some sort of hazardous devices ready to explode at the most inexpected time?

[1] https://www.youtube.com/watch?v=62wUaJUh4Ko

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wtallis 959 days ago
Those batteries are glued in to their own rigid case, which makes swapping them out of the laptop trivial but also didn't leave much room for expansion inside the battery pack, and the battery pack was pretty thick compared to any recent Apple laptop.

Replacing the cells inside one of those packs would have been similarly difficult to ungluing and replacing the batteries in more recent Apple laptops, but there was a lot less reason to rebuild those battery packs.

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