Can you share your R5 battery expertise?

[pedz]

I figure you guys actually know, first hand, what hardware is inside the Canon R5.  There is a debate on another forum about batteries and how best to store your camera.

What I plan to do in the future is to store the camera without the battery.  If I store the camera with the battery in it, the battery discharges within a few months.  My experience is with the R5C but I assume the R5 also has this characteristic as well.  I just haven't stored my R5 for as long a period.  Also, it seems that the Bluetooth is always on unless turned off via menu settings.  Possibly the Wi-Fi works similarly.

I assume the settings are in some type of non-volatile memory and should survive indefinitely without power.  Someone pointed out that there is a button battery that keeps the clock running and it could go completely dead and is not cheap to replace.  They also claim that this button battery is recharged from the main battery.

I would assume the button battery powers the clock all the time and I would also assume that the main battery does not recharge it since batteries that last a long time such as button batteries are generally not rechargeable.  Perhaps the main battery takes over the job when it is installed.

Can you share your knowledge?

[names_are_hard]

It's easy to find that Canon has previously used non-rechargeable CR1220 cells a lot for RTC batteries.  Do they use one for the R5?  I don't know.  See if there's a teardown video, you might be able to spot it.  Or crack yours open if you feel like it.

You may well be wasting your time regardless: have you checked if the main battery discharges faster inside a cam compared to outside?  Most rechargeable batteries will lose a lot of charge if you wait a few months.  Personally, I'd still always store cams without batteries in them - it won't lose charge faster, and batteries can (rarely) leak.

[yourboylloyd]

Don't know how much of help I will be as I don't have an R5, but on my R6 I've gone more than a month without using the camera and haven't noticed any difference in battery life (I'm sure there is, but practically it didn't matter for me).

[Walter Schulz]

CR1220 is a thing of the past. I think 5D3 was among the last having those non-rechargeable clock batteries which where accessible via main battery door.
Canon switched to rechargeable LiON type named MS614 and manufactured by Sharp*. I haven't found any camera where those are soldered**. They come with a battery casing mainly consisting of white plastic. They started with battery holder soldered to mainboard and facing rear panel. Battery is accessible after removing back plate. Some newer models have holders facing to sensor. To replace clock battery you have to remove mainboard and therefore all cables attached. Models like 200D/250D are odd because battery is *not* part of mainboard but placed somewhere beyond.

If battery casing faces rear panel replacement should be easy. Just remove some tiny screws and remove rear panel with care. In most cameras there are two cables connecting rear panel. One FPC/FFC ("ribbon cable") with a board connector attached making plugging in/out a non-problem. Other connector is mostly a full-metall type dedicated for display connections. You will find them in laptops, too.
There are exceptions to the rule. Some cams (EOS M!) have an FPC/FFC direct plug to some header. It is a common mishap to damage this one and replacing it is a real PITA!

Now about R5:
This one has indeed its clock battery facing sensor. Requires cables connected to mainboard to be disconnected and there are a lot and handling them may not be advised for everyone. See Lensrental's teardown: https://www.lensrentals.com/blog/2020/09/taking-apart-the-canon-r5-mirrorless-camera/

Link to picture:
https://www.lensrentals.com/blog/media/2020/08/5T5A0077sml.jpg
Those three fingers at PCB's bottom? Battery and casing/holder are just at the 2nd finger.

Minor good news: Rear panel is connected by a single "ribbon" cable with board connector attached. You have to be extremely clumsy to rip this one apart.




* Other manufacturers switched to "Super-Caps" which is a fancy name for capacitors able to hold a very large charge. Those won't need any maintenance.
** There are MS614 varieties with solder tags welded to battery. Those won't fit!

[names_are_hard]

Thanks, that's good to learn, and annoying.  Now I'll have to make sure I regularly put a battery in my modern cams - LiON batteries permanently die if they fully discharge.

[Walter Schulz]

Bummer indeed: 200D, 850D and 7D2 require to have mainboard removed to access clock battery.

[Walter Schulz]

Found Kolari Vision's teardown of R5C. Yes, there is some work involved but battery replacement can be done by any sensible person.

https://kolarivision.com/canon-r5c-teardown/

The Canon EOS R5C was easy to disassemble, as it was structurally similar to the standard Canon R5 camera, except for having more screws, according to our camera technician Jared.

EDIT: I found no picture of R5C's mainboard rear to confirm it uses an MS614, too. I would be surprised if it is not there but no proof yet.