I've found the answer regarding difficulty in removing the inner from a BT-DN 110a, see my earlier comment . After carefully slitting the outer case, with a Stanley knife, I was able to use a sharp pointer to prise the inner from the end of the case. I then found the a double side sticky pad was used to fix the end battery to the case. It maybe be possible by very careful drilling hole (say 3 or 4mm dia.) in the end of the case to push the inner out without the need to first slit the case.

Excellent job -- these packs are 125 euros where I live and this is a great solution.

Thanks so much for the demonstration. I have the same issue. Batteries ordered.

Thanks Davie. Really good explanation and it needs to be. I'll give it a go with my 110 and if it doesn't work...I'll buy another. Try first, cry later!

cheers Davie . just did mine in 15 mins !!

I replaced my batteries with new cells from Digikey. $3 each. I welded on my own tabs on the batteries and found the tabs and solder joints need to be tidy or the assembly won't easily fit back in the case. For $6 my Di2 is back in action.

TY for this tutorial!

Hi and thank you for the reply. It was worth asking.

Great video!

Thanks for the video. I have a charger for other lithium batteries. My question is at the end of the assembled battery could one connector to positive and negative?

Nice!! I’ve ordered some cells and will be doing some soldering.. mine lost all its charge after 1 ride and I’m not paying £149:-)

Great job. I love this stuff. Thank you for sharing. I'm honestly sad at the Shimano design, I think it's rubbish, but I might still buy it because SRAM has a few things that are not perfect also.

Magic thanks man

Hello, Thx a lot I want to charge the bike for the good wheater this weekend & there where no lights on the charger and the DI2. Just ordered 2 pieces. We will try it out :-)

Hello, I have some question about Di2 Battery connecting area. Beside cable connector (coaxial) we could see some kind of copper plate (lamella) I think it could be for "hard reset" of battery. Disconnecting cable make this late in contact with outer of coaxial connector. Right ?

thank for your vido.I successfully revived my 6870 and saved 85＄on battery🥺

Hello I would like to use a Shimano Alfine 11Di2 for my e-bike muscle drive part, but I don't want 3 batteries on board (so far I have 2 GreenPack to power 2 Grin AllAxle motors). I would like to know if it is possible to power Di2 differently than from the original Shimano battery? For example, using the Shimano EW-EX010 adapter normally used with Bosch systems. However, no one can tell me what the plug at the end of Bosch Y-Harness is (the one that plugs into EW-EX010) and what pinout it has. I suspect that I will have to reduce the voltage from 48V on the GreenPack to a 36V Bosch battery and I will not have a CAN to control the automatic gearshift (no cadence and speed sensors for the muscle drive). Or maybe do it differently ????

Thanks for the great video! I missed the part where you opened the casing to reveal the batteries. Is that on the video?

Good tips. But. Dismantling mine, find batteries were 100% despite being 4 yrs old, it was the little PCB on the pack that fried. For that there's no fix but to but a new £120+ rip-off priced pack. The E-tube confirmed the master unit wasn't visible, until the DN-110 smart battery was plugged in to the system

Just fried my battery. It wasn't holding charge well and I decided to replace cells. Opened it up and started to carefully peel tape. Suddenly got a whiff of smoke from the board. Put everything back - Di2 is completely dead and not charging (charging light doesn't come on). Not sure what could happen. Is it possible Shimano added some tamper protection to newer batteries? BT-DN110 from 2016 Meanwhile my bike is dead until new battery arrives... :(

Great video Davie... inspires me to tinker with my BT-DN110A batter pack that is no longer holding a charge. Only problem is that I am unable to source the 14430 batteries required to fit the battery housing. I was contemplating using the 14450 batteries... they have the same 3.7v but higher mAh.... in your opinion, you think this could be an issue? I was thinking of just building a new housing for the slightly longer battery if the configuration works with the chip.

Hi have a good friend going to follow up with your nollage a good video jerry

Many thanks for a great video. I've have a BT-DN 110a that I am unable to remove inners. I've put forks in the groves at each end of the case and tapped these with a hammer. I've also tried gentle heat, which may release glue, but with no effect. The only thing I can now think of is carefully cutting the case. Do you have any suggestions? Kind regards Pete

great stuff, wonder if it'd work with the newere DN-110 batteries...

Great vid and good to see the art of entrepreneurship isn't dead. Only 1 comment, you said the batteries were connected in parallel (at 1.25) but they must be in series if they're both 3.7v and give a total of 7.4v? If in parallel the total would still only be 3.7v. My only query is if they are in series, why have a separate 3rd wire coming off the centre connection between the 2 batteries? I can't understand what that's for....anyone?

Bom dia dia,pode me passar o link de onde conseguiu essas bateria de 650ml

Wish I saw this 3 weeks back and would of saved me £165 🙈

Davie or someone, have you managed to do the same with the newer Shimano Di2 BT-DN110 model? I am having a hard time "opening" the housing... It does not have the tabs to push in to release the housing...

I wonder if this will work the the A version of DI2 battery. As in the BT-DN110-A for the Ultegra DI2 8050 which i have. 95 pounds Sterling for what amounts to 2 rechargeable batteries is a bit steep. Thanks for this. I bet the battery suppliers listed are happy. On their site they say in the description that this is for 6870 Ultegra though.

My DN110 doesn't show up on the pce2 and when trying to charge and the light on the main charger doesn't appear. Opened up the casing and the voltage was 6.16v. Tried to push up the voltage for both and for each battery using 12v but not really moving much 6.56v. I would have thought the unit would still be recognised with 6.16v so before I start thinking about replacing the batteries, any idea if the CPU is most likely at fault? The charger is getting power to the batteries but not charging them I believe. Both batteries are over 3v.

Top job, no way I am giving Shimano £160, its just robbery.

I tried this, and now it doesn't work anymore. It still communicates, but it doesn't give any power anymore. 😞

Can anyone help, problems with Di 2. After testing the battery., pressing the lever, solid green light comes on followed by the red three seconds later, green and red lights are on together. What does that indicate? Rear mec is working but front mec isn’t,t . Battery is showing 7.5v . Can anyone help

Just out of curiosity how long does a battery pack normally last does anybody know

Not to criticize but if you use a better solder iron you would get better and faster results with your welds. Using that iron you are holding the heat on the battery longer trying to get the solder to melt, that is not good for the battery. I see those batteries came with tabs on the ends. you only need to solder the tabs together between the two batteries and not try to solder the batteries together. I have experience building battery packs mainly using the 18650 cells but they are basically the same. I do appreciate you posting this video because it will save me money when it comes time to replace my Shimano battery. I will give this a go

after replacing the batteries, unfortunately, the whole assembly stopped working :(((

Writing here because I haven't found any help on the internet I replaced the cells in a battery that stopped holding charge for more than 24h. Essentially, I did the exact same job as shown in this video. The problem is that the di2 system pretends my battery is dead despite it being charged. I can charge the battery with the normal di2 charger, everything seems fine. But when I try to shift, the junction box blinks 5 times red - meaning the battery is dead. Except it isn't, both cells are at 4.2V My guess is that the microcontroller of the battery decided it was dead (either for safety or just to stop you from repairing it, Apple style) and refused to change gears, since a big part of the brain of the di2 system is in the battery I tried updating the firmware of the battery using the SM-BCR-2. I hoped that updating the firmware would "reset" the battery, but while I managed to update it, it still refused to power the system Also worth noting, the shifting works when the charger is plugged in, but won't if the charger is plugged in but not the battery. So I know the battery can physically work but won't

Hi are you open to refurb my batteries ? I will pay obviously. Please get back to me when you can. Regards George