Spare battery has swelled!?!

When I bought the X-T1, quite a few years ago,
it came with one original (Fuji) battery. I wanted
a back-up battery as well, and picked a Patona
(having a much nicer price).

I have used both of them regularly, and charged one
while the other sat in the camera.

Until today. The Patona has swelled so much that it
cannot be inserted into the battery chamber any longer.

Is this quite common?
Is it due to the fact that I bought a cheaper brand?

Have fun!
Claes in Lund, Sweden

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I’m willing to bet it’s a cheaper (manufactured) battery. This seems to happen more often in third-party batteries unfortunately…

Here in the states there is a 3rd party company called Wasabi. I’ve had zero problems with their batteries.

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In this post (in German), an original Olympus battery and one from Patona (and a no-brand one) were dissected. The OEM battery had a much better design than either third-party battery, with solid casing, nice electronics, and a bit of margin for swelling.

(Google Translate)

Patona installed the best cells. A decent electronics like Olympus and they would be absolutely first choice - even for the price of an original battery. Despite the defective battery, Olympus delivered the best manufacturing quality. Everything is in its place, everything is as it should be and the whole thing is safe. You can see it: even leaked electrolyte cannot inflate or set fire to the battery case. This is because Olympus realized the gluing with foam rubber strips on the edge, not in the middle. And that’s why the bags can inflate up to a millimeter on both sides without anything happening.

[…] The Patona can be considered as an emergency replacement if you don’t use it more than once a month. Then you will also last for the life of the camera. Because the Patonas are actually killed by the charging electronics. As long as you don’t [charge] them, they are great….

On the electronics found in the two third-party batteries:

After all, the cells have a center tap, which is led to the board on B1. Unfortunately, it goes to a 470 ohm resistor and not to a charging electronics, which explains the short lifespan of the batteries. Again there is no load balancing. It was already clear that there was no thermal resistance.

Be careful! A swollen battery may explode – one reason for battery swelling is that gases are released inside it. I’d take it to an e-waste disposal site as soon as possible.

Also see:


Have a look here and here
Very nice documented and explained.

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YMMV, I have an OEM Sony battery and two 3rd party Patona batteries. I’ve used them extensively for the last three years and sometimes I even think they last longer than the original one.

Thanks for instructive links! Brrrrr.
One of the revealing things I learnt is
that Patona seems to have a resistor
in a position where the original has
a thermistor. A small thing, yes, but
since the thermistor assists in cutting
off charging if the thing gets too hot,
the lack of it does not sound sufficiently

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Yeah, sometimes knowing to much is not good :wink:

… and knowing too little can be lethal.

I followed @mbs’ advice and took a trip
to the city’s e-waste disposal dump this
afternoon to get rid of it. Just to be on
the safe side.

From now on, only genuine, original parts for me.

Thanks, all!

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Safety first. Not all batteries are made equal, even from the same manufacturer. Same with other hardware like cameras. There are bound to be duds. Sometimes I get unlucky a few times in a row.

Yes most probably the cheaper one swells up really soon. In case of batteries we should never ever consider cheaper option. Even with cheaper batteries we are damaging our devices as the voltage are not accurate enough and there are many other things. So we should always buy a genuine battery in case of our devices.