I’m going to make an external pack for the Rytm. I grabbed 6 1920s thinking I can get longer life.
Anyone have some info on how I could use the same BMS with twice the batteries?
Would I just run pairs of them in series before connecting as directed?
Create two packs in series, so that each one of them can power the device, then connect them in parallel. I doubt that this will fit into a Rytm though.
I’m going to end up 3d printing a holder and velcroing this outside the rytm. Not housing it internally.
I originally bought 6 batteries to make an internal battery for a Digitone and make a spare to sell or give to a buddy.
I no longer have the digitone so I figured “what the hell, let me double up on mega pack and hopefully get a few hours out of the rytm.”
Just to clarify. Are you suggesting making two separate packs with separate BMS boards then running those in parallel?
I suppose the main things I need to get right are volts and amps. I’ll play around with a meter and see what combos keep me in the right range.
My assumption was that I could run 3 pairs of batteries in series to act as three “bigger” batteries. Bigger in this case meaning more mAH and longer life. But ideally the voltage stays the same.
E: I found this.
Has anyone tried with a syntakt yet ?
Also, is there any current (best) write ups or a pre assembled battery pack sold?
I’m thinking about adding a battery to my Digitakt.
How have people been getting on with the mod? Have the batteries stood up ok? Any unexpected issues?
Thanks
Chuggin along great 
I wish somebody would make an external WEDGE SHAPED USB battery. I can’t realistically do this battery mod because time poor and crap at soldering. I use external USB batteries with myvolts but they are clunky rectangular objects.
Air you thinking something that sits under the box and props it up at an angle?
Exactly. I would love external batteries to fit in with the device a bit less clunkily. I guess the geometry would be different for different devices. I’m just finding I use devices with internal batteries more than any other. So opz m8 deluge get used, octatrack blackbox get neglected, even tho I love octatrack. It’s the octatrack especially that I’d love to make portable. Lack of battery is also my main reason for not getting digitakt.
~1 year after installing an internal battery (thanks to instructions here) I finally pulled the trigger and decided to do it for my OT MKII as well. This time I was able to find the components through Amazon with a next day delivery option. A couple of £ more expensive but it was worth it since I didn’t want to postpone this until the next weekend.
I was able to fit 21700 batteries into the space under the crossfader, wired up to a BMS board sitting on the empty-ish PCB space just in front of it (ofc everything is properly insulated). It was a bit challenging to fit the batteries in but I managed to avoid using a battery holder and get away with some heatshrink wrap and electrical tape. I’m expecting a solid 5+ hours of battery life. Currently charging. I’ll keep you posted regarding the battery life (if I ever can make it run out of juice).
P.S: I also got a tiny BT transmitter. I tested pairing it to Airpods Pro and the latency feels like roughly ~80 ms even though the transmitter just supports SDC codec (it was close to 200 for other BT headphones I have somehow). For live recording melodies it would be too much latency, but it’s more than enough for “arranging” imo. Finally I can enjoy a fully “cordless” setup on my couch, which was my dream 
I think this is great but be aware that in the long term, even without exposure to heat, electrical tape starts to turn into the black death goo. you may want to revisit those parts at some point and wrap them in something that it won’t matter if they get gooey or sticky with residue.
Yep, I plan to do to at least yearly checkups. My DT mod didn’t even have shrink wrap but just electrical tape, I just checked it today and it’s literally how it is on day 1. It’s a decent quality tape.
without going back and re-reading this thread did you use a buck converter to bring the li ion’s up to 12v?
nope I just used 3x 21700 3.7V 4000mAh flathead batteries. The batteries I’ve got for DT charged upto ~12.3V, in the case of DT I was able to keep it alive until it’s as low as ~10.9 and eventually getting frozen after ~4.5 hours (they “supposedly” were 5000mAh tho). According to this thread, OT can go even lower, let’s see!
P.S: I’m just using regular Elektron PSU btw. These last batteries I’ve bought were somewhat charged (measured 11.5V combined) and they worked right out of the box. For the batteries I’ve got for DT (they were very suspiciously looking cheap ones from a random Vape Shop), they didn’t any show any signs of life initially, and they measured ~10.4V combined. I lost all hope but then I left them on charge (again with Elektron PSU, while they’re still fitted insite the DT) for a night straight, and everything was working brilliantly the next morning. No problems since that day!
Hey all, random note, but as I stopped using the internal battery (chinese BMS modules are just too unreliable and kept failing me), I now use Digitakt and other devices with an external USB-C pack.
You can build your own USB-C PD step-up cable to get 12v on a digitakt compatible DC barrel jack. It just means soldering a 2.5mm connector to the end of a USB-C Trigger module that draws 12V: USB C Pd Trigger Board Module Pd/Qc Decoy Board Snelle Lading Usb Type C Om 12V Hoge speed Charger Power Levering Boost Module| | - AliExpress Tiny, inobtrusive, no need to open the device.
You just have to make sure you have a powerbank that can do USB-C PD 12V (usually 18w or 36w). You can also power it from a regular USB-C wall power plug too, as long as it can do the right voltage. My official Elektron adapter is not used at all anymore.
More info here: USB-C Power Delivery - Everything you need to know
That’s sort of what I’m doing with my ST (because of the lack of space inside for a battery). Baseus 12V usb-c powerbank velcroed on the back if ST and connected via a birdcord cable.
you have a picture of that one?
it’s a collector’s item! and looks good, the cable is the only thing that protrudes to any extent. I expected that this would require a fairly physically large power bank. Looks like I’d have to find another kind of stand than what I currently use in order to work with one of those.
I’ve been thinking about using the vesa holes to panel mount my DT and DN into a more permanent unison, maybe there’s a way I could use that to my advantage, I guess it’s possible I could figure out how to replace my stand’s back brace with the larger vesa mounted panel. So is there an estimated run time off the Baseus? is there another 12v model you saw with a higher storage capacity? Thanks for the information you shared and for posting the pics.
