3 hours ago, Davide DB said:

I did a quick test of the first option, connecting the camera with a full battery to a normal USB charger.

Upon connection, the camera warns you that the connected power source is weak and can only charge the battery when the camera is off.

I started recording in FHD (otherwise I would have filled the card) and after 50 minutes the recording was still going and the battery was still at 100%.

When the USB charger was disconnected, the recording continued without issues, using the battery.

So I would feel confident in confirming that a couple of small batteries in parallel with a step-up converter with the proper protections would be enough.

In my housing, the main problem is space.

Yes that's at 5V from an Iphone type charger, wondering if it might work better with two batteries in series as the readily available batteries are 3.7V.

Did you check afterwards did it draw power from the onboard battery or from the charger, the battery reading after pulling the plug will tell you? Your housing it seems has space for the mini flash and if so I would think you could readily fit two 18500 batteries in there and if the battery holder is not too big that should also fit and that's effectively a second battery. You probably won't have the issue mentioned in the video if you just use batteries without the voltage step up.

The 18500 batteries are short 18650s and are 50mm long. It seems like that option could be quite doable with minimal work apart from attaching a USB cable to the battery carrier and it looks like there is enough space where the flash trigger would go.

6 hours ago, Chris Ross said:

Did you check afterwards did it draw power from the onboard battery or from the charger, the battery reading after pulling the plug will tell you?

Yes once the usb-c was removed, the camera continued flawlessly recording using the internal battery, so it's a completely use case from the video you posted. Here the internal battery act a sort of last reserve.

6 hours ago, Chris Ross said:

wondering if it might work better with two batteries in series as the readily available batteries are 3.7V.

Good question, I guess it depends on how much current the camera draws while recording. So I can choose between serial or parallel circuit. I haven't a tester here now.

I'm not at home so the only test I could do is putting the camera battery in that space.The battery (55mm) fits only lengthwise, and just one millimeter more and the housing won't close. So with the 18500s, I wouldn't have space for the battery holder. If I use "bare" batteries instead, I have more freedom of choice.

Another option is using LiPo packs that usually have squared shapes.

45 minutes ago, Davide DB said:

Yes once the usb-c was removed, the camera continued flawlessly recording using the internal battery, so it's a completely use case from the video you posted. Here the internal battery act a sort of last reserve.

Good question, I guess it depends on how much current the camera draws while recording. So I can choose between serial or parallel circuit. I haven't a tester here now.

I'm not at home so the only test I could do is putting the camera battery in that space.The battery (55mm) fits only lengthwise, and just one millimeter more and the housing won't close. So with the 18500s, I wouldn't have space for the battery holder. If I use "bare" batteries instead, I have more freedom of choice.

Another option is using LiPo packs that usually have squared shapes.

I think the benefit of using some type of holder is you don't have to worry about battery management for charging.

I also found this one and 18350 which is 35mm long 18 dia, might be able to do something with them, but you'd need four of them. Ali express has holders .

https://www.liteshop.com.au/content/nitecore-nl1816r-1600mah-usb-c-rechargeable-battery/?gad_source=1&gad_campaignid=17182817440&gclid=CjwKCAjw2brFBhBOEiwAVJX5GD8NqXpZ7sSwOyl6OeguSdGD1zIFkTQVEi74Q9Cvz1gm6ajRUxZmeRoCXxoQAvD_BwE

1 hour ago, Chris Ross said:

but you'd need four of them.

Why four?

3 hours ago, Davide DB said:

Why four?

I think the capacity would be a little on the low side with two, 11 W-hr which is less than the on board battery, but it's not essential I guess.

On 8/27/2025 at 6:31 AM, Chris Ross said:

I think the capacity would be a little on the low side with two, 11 W-hr which is less than the on board battery, but it's not essential I guess.

If you go back to my post from Aug 21; that shows my 3 battery 18350 solution for the Canon V1.

Edited yesterday at 02:25 AM1 day by insomniac

1 hour ago, insomniac said:

If you go back to my post from Aug 21; that shows my 3 battery 18350 solution for the Canon V1.

Yeah I saw that, a nice solution, I'm thinking for people who aren't as comfortable spot welding battery packs together and if they have the space installing the same batteries in a holder that would be a good solution as you probably don't need any balancing for the batteries as you can pull them out and charge them in a dedicated 18350 charger, so you don't have to be concerned about getting them all fully charged.