Powering the Canon EOS-M with Anton-Bauer Gold Mount Batteries

EDIT: When this was written in early 2015, Canon made very little effort to publicize their AC adapter for this camera; it is almost as obscure as the access point (the rubber grip on the battery door simply flips open to reveal an access hole for the adapter plug).

Shortly after posting this article, a commenter admonished this hack and pointed me towards the correct adapter – the Canon ACK-E12. In the meantime, the market has become flooded with endless Chinese ripoffs of the ACK-E12 for $11-15, which do the job much better than anything you see written below. You should still expect to perform modifications though; the ACK-E12 adapters are meant to connect onto an AC adapter, not a DC coaxial plug. In my case, I simply cut the existing line I had built and soldered it onto the ACK-E12’s leads. With a bit of heat shrink tubing, this solution worked exceptionally well.

Please consider the above before making any such modifications. The remainder of the article here is provided for reference. 

For better or worse, I’m partial to using the Canon EOS-M for shoulder-rig run-and-gun/event videography. While DSLRs or mirrorless cameras may not be the most ideal choice for the purpose, I find the EOS-M to be simple and convenient – and, unlike my Blackmagic BMCC/BMPCC cameras – it has the capability for auto ISO (and thus auto-exposure).

However, the limited battery life of the EOS-M’s LP-E12 has been the only limitation of the camera. Unlike the 5D Mark II, a dummy battery is not available for the EOS-M, and the battery door does not have a provision for an external cable – not without modification.

I happened to have two dead Wasabi LP-E12 knockoff batteries taking up space, so I decided to remove the battery core out of one and see if it would be possible to modify it.

These photos are for example purposes only. Opening up any electronic device as shown will void its warranty and most certainly cause possible injury or death to your person and/or others. Doing so will also ruin your sex life forever. Do not try this at home or on the moon. Your stupidity will never be my responsibility in a court of law, because you free me and everybody else in the world of liability if you even think of doing what you see below – or actually do it, or anything remotely similar.


The Wasabi battery casing derives most of its strength from the battery inside it. In comparison to the genuine Canon LP-E12, it is not very good. But it’s good enough for what we’re doing here.


After reinforcing the case with some styrene…


A connector from another electric accessory donated its power cable. The wires on this end were modified with brass sheet soldered to them as contacts. The other end has a female connector that interfaces with the 7.2v connection off the Chinese Gold Mount adapter for the Anton-Bauer battery.

A little more fiddling (not to mention some more Plastruct glue and some reinforcement styrene) got me to this point, with both contacts melted between two sheets of plastic to ensure that they’re not going anywhere:




Now the painful part – notching the EOS-M battery door. These doors cannot be replaced like the 5D Mark II. Has to be right the first time:




Perfect – but does the camera work without the battery ID sensor chip in the wiring?


It certainly does! The photo of success. The battery level indicator shows a full charge, which this Dionic 90 had when pulled off its base:


Ready for this Sunday:


And that completes it. We’ll see how well the setup works, but I expect it to work no different than a remote battery setup for a 5D Mark II.

-Man with the 5D

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James BondKurtKurt K.Kaiju Recent comment authors
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Actually, from what I have read, the eos m and m2 does have a spot for a dummy battery. the black rubber spot on the battery door swivels out of the way.


Kurt K.
Kurt K.

You’re certainly right. Never noticed the trap door until now.

Strange thing is, I tried desperately to see if such an adapter existed before I modified the camera – and came up with nothing. This is the first I’ve seen of the actual dummy battery and adapter.

Thanks again for the link.


James Bond
James Bond

I got the same problem but on EOS-M3 wireless make the battery go’s flat about 20 minutes but look going have same problem on the NEW Canon EOS-M5 as there is no provisions ether camera only provisions there is in the battery cover that for the AC but the is too small for a dummy battery

James Bond
James Bond

Yes there is a rubber flap on battery flap but hole is too small for a connector go though and even if you get dummy battery from eBay cable is in wrong place as blocks the catch to keep battery in place as I going use my dummy battery for “Tether Tools Case Relay system” but you still have to make hole in the camera or on battery flap

James Bond
James Bond

UPDATE EOS-M3 & M5 Dummy battery – Tether Tools – Case Relay I found way use it on EOS-M3 & will also work on the M5 when comes out November 2016 if you get the Canon ACK-E17 AC Adapter Kit inside the box their is a dummy battery with small pin jack hole so you can use it on the “Tether Tools – Case Relay” inside that box is a right angle cable to fit this dummy battery (I do not know what the cable called or the code for it) you put in on bottom camera flip the plastic… Read more »