DIY Battery Extender For Meikon Housing

Hi guys,

I have recently purchased a Meikon X-T3 housing - I think it's great for the price (so is the camera). My biggest gripe with the camera is the battery life.

Considering my options:

1. Buy Nauticam extender - Expensive and I'm 90% sure it wouldn't fit. Space is rather limited inside the housing.

2. Make a DIY battery - Much cheaper and can be made to size. I'm thinking 1 or 2 18650 batteries connected to the USB-C port somehow or via a dummy battery.

Only problem is I have no experience with electronics in this way and I have no idea what would be safe - which is obviously my primary concern.

I would rather buy different things to piece together and avoid soldering if I can.

Any help would be greatly appreciated!

For an idea of how much room I have (conservative measurements):

- Above the camera where a flash trigger would go I have a rough measurement of:  55mm x 35mm x 20mm (or 40mm x 2.5mm x 5mm if positioned in a different orientation).

- Below the camera (where there is currently a leak sensor) I have roughly: 70mm x 50mm x 10mm

Thanks

First of all you would need two 18650 batteries to get the required voltage, the XT-3 battery is 7.4 V and the 18650 3.7V.  I think the goal of no soldering may be a little unrealistic.  Googling I also found this: https://www.newsshooter.com/2019/04/29/powering-the-fujifilm-x-t3-with-usb-c/  The batteries it mentions seem to be too big to fit - but what it does say is that the XT-3 in finicky and won't run off just any USB battery. 

You need to consider a number of things - is there enough space to plug in a USB-C plug in the camera- the most straight forward way to connect up.  You can get 18650 battery holders :https://www.ebay.com.au/i/312989008026?chn=ps&norover=1&mkevt=1&mkrid=705-139619-5960-0&mkcid=2&itemid=312989008026&targetid=1087152002312&device=c&mktype=pla&googleloc=9071894&poi=&campaignid=9767734220&mkgroupid=99377634146&rlsatarget=aud-786643581326:pla-1087152002312&abcId=1145981&merchantid=7364522&gclid=Cj0KCQjwka_1BRCPARIsAMlUmEo-D-Sgzvkp4qHRUrPmGwrLxKoLSlhGDOjveC6O8svUEtt0WPOeQ4waAlA_EALw_wcB

You can also get a DC coupler for the XT-3.  Have a read through this link, it provides lots of options including a pre made up DC coupler:

https://domvarney.com/2018/11/22/powering-the-fuji-x-t3/

There is a section on battery banks and also the DC coupler.  Without electronic knowledge I would suggest you best approach might be finding a battery bank which you can connect to the camera via USB-C that fits and also supplies enough power.  You would probably need a right angle USB-C cable to connect.   Next best option is doing something with the DC coupler, you may need to solder a plug onto a 18650 battery holder to connect up.

It seems the high wattage is needed when recording video compared to stills so if you are primarily shooting stills you could get away with a smaller bank.