Sony NW-A105 is a very well-known Android DAP that was released around the end of 2019. As discussed in many forums (head-fi forum) and reviews, a significant downside of this Android DAP is the Battery life. Some members in the forum even shared steps to disable background services and run the DAP in airplane mode which helps improve the battery life, but it is still mediocre.
In this article, I will share on how I mod the battery on my A105 to increase the battery capacity.
The major idea here is not about the software optimization to prolong the battery life but to increase the battery capacity by adding a second Lithium Ion battery to the DAP.
Battery Wire Soldering
For the dissembly of A105, the right way to do it is to gently slide a thin plastic card to the bottom corner of A105. And slowly move toward the upper part of the back cover.
It’s not too hard to open the back cover, and the adhesive location is as marked in the image below. The back cover of A105 is an L shape that extended to the top part of the DAP. There are some latch on the top part of the cover.
The location of the screws is as follows. You have to first remove the 2 x Antenna Screw and remove the antena module.
After the Antena Module is removed, there will be another 2 x Battery Cover Screw beneath.
After having all 4x Battery Cover Screw removed, the Battery Cover can be removed. Take note that the Battery is actually adhesive onto this cover, so do not pull too hard to avoid damaging the wiring connecting the Battery to the PCB.
From the sticker on the Battery, the battery capacity is 1285mAh, which is quite small, the latest android phone has up to 5000mAh battery.
There are a total of 3 wires soldered from the battery to the PCB Board. By using a multimeter to check, Red is the +ve terminal, Black is the -ve terminal, and White is for the battery’s Temperature sensor.
In order to add a 2nd battery to the system, we will need to solder another 2 wires to the +ve and -ve terminal to “Parallel” the +ve and -ve terminal of the internal battery and the 2nd battery.
You will need to be very careful in this step as the +ve and -ve terminal is live wire from the battery and makes sure that when you heat up the solder, the wire did not goes loose and touch another metal part on the PCB. Also when your soldering gun is in contact with the terminals, the soldering gun itself is also connected to the battery terminal either +ve or -ve terminal. When I am working on the soldering, I accidentally disconnect the battery from the PCB, and when the battery goes back in contact with the PCB, the Player Turn ON itself, but luckily it did not cause any damage.
You also need to route the wire through the small opening as in the photo below. You can use any wire colour, but need to make sure that the wire is small enough to be easily routed.
In order for these wires to go out from the A105, we will need to have a hole on the back cover. I punch a 3mm hole using a normal drill on the back cover around the area where the wire should come out from the A105 body.
With the hole done, you can now route the 2 wires through the back cover. I will advise doing a quick test on powering up the device, just to make sure that the device is still working after the soldering job. And if all is good, you can assemble back your device. I also replace the adhesive for the back cover. A little IPA will help in removing the old adhesive from the back cover and the battery cover.
Second Battery
The second battery selected for this mod is the battery from Samsung Galaxy S5, which is rated at 2100mAh. The physical size matches the A105, and by adding this battery to A105, the total battery capacity increased to 1285 + 2100 = 3385mAh. Although this is not as big as 5000mAh, but I believe it should extend enough battery life for A105. Almost 3 times compare to the original capacity.
The size of the battery fits A105 perfectly, and its thickness is around 6mm.
After A105 has been assembled and the 2 wires routed out from the back cover, we need to solder these 2 wires to the second battery.
Voltage Level Concern
Before connecting the second battery it is important that both the 1st battery and the 2nd battery is having similar voltage to avoid voltage differences when the wire is connected. In order to do this, you can read the voltage for the 1st battery from the 2 wires using a multimeter, and charge or discharge A105 for the 2 voltage to reach the same level. I will say that it should be good enough if the voltage difference is less than 0.1V.
Now you should apply some solder to the copper terminal on the battery. Take note that there are 4 copper terminals on the battery, and the +ve and -ve terminal is normally labeled. You can use a multimeter to verify the terminal.
Carefully solder the 2 wires from the A105 to the battery, and leave enough length to ease the soldering work. Again, take note that these are live wires, do make sure that you connect correctly, and do not short the +ve and -ve terminals.
Back Cover V1
Now that the 2nd battery is properly connected to the A105. We should move on to the back cover. Initially, I designed a very simple back cover that is rectangular and follows the size of A105.
I 3D printed the part, and adhesive it to the back of the A105 using double-sided tape.
Functionally it works well to hold the battery but aesthetically it did not look nice. First a 3D printed part is not really of good quality, and the boxy design is not really nice and does not match A105 nicely.
Back Cover V2
To improve the design, I now add some chamfer to the back cover. The chamfer at the bottom of the cover gives a better grip when holding the A105 in your hand.
For this design, I 3D printed a prototype to test all the sizes and check if it match A105 properly and I send the drawing for Aluminum CNC Machining through PCBWay (pcbway.com). On their website, you can upload the CAD file, select the machining material, and even the finishing. I went with aluminum 7075, and Black Anodized finish. The total cost of the part is around USD48 + USD15 freight cost (shipping to Malaysia). It is not really cheap, but the result is very satisfactory.
The part received from PCB way is really an upgrade in terms of quality and the finishing surface vs the 3D printed part. It matches my A105 perfectly, with the Black Anodized finishing. I used thin 3M double-sided tapes to adhesive the cover to the back of A105.
It increase the thickness of A105 from around 11mm to 18mm, (the battery is 6mm thick and the cover is 7mm thick in total.
I never really timed how long the battery can last, but it is very safe to say that it lasted around 3 times compare to before the mods. I can now comfortably steam through tidal and spotify without worrying too much about the battery, I charge my device around once or twice weekly and have around 2-3 listening sessions per day.
For those that own a Sony NW-A105, I really recommend you to try out this mod. I think the only challenging part is the soldering steps as we will be dealing with the live wires. Please be extra careful on that step.
You can find the CAD file attached at the bottom of this article. I included the Solidworks part file, and STL file if you want to print out the parts. Also please comment or give suggestion if you have a better idea about this mod.
So cool. I’m a beginner so not super confident I can fit his and don’t have soldering equipment yet. What is your recommendation here?
Thank you for your interest.
To be frank, the soldering part is quite risky, the worse case is that during the soldering, the +ve or -ve terminal shorted to another part of the PCB that could damage the DAP, or if you short the +ve and -ve terminal of the battery for a longer period, there are risk of fire.
If you are not confident, I suggest getting someone working in this line for the modification.
Awesome post, thank you very much.
Did you consider to completely remove the original battery and utilize some pogo pins in a custom housing to have an interchangeable battery as well as a smaller housing?
I would bet, that a 3d printed backplate with a modified /drilled metal housing for the battery would allow to use a thicker but shorter battery to fit completely into everything (like the PS5 controller, LIP1708) and also would be much thinner in total.
The problem you may get with your solution is, that the different BMS of the two batteries will prevent equal charge / discharge resulting in overdischarged batteries or random power loses when the batteries are getting older.
Thank you for the suggestion.
Just curious… I have the new a306 and have been thinking of ways to optimize the battery life. There are batteries about the same (or even smaller) size that contain up to 3800mah. I use one in my modified iPod. Just curious if I remove the original battery and swap it with something else entirely would the lack of a temp sensor line be an issue? Perhaps I’ll get an a105 to test with first.
Hi Arin, I did previously think of replacing the battery with another one, but that will require hacking the original casing further, which I think is a bit too much modification. I am also worry that it will affect the original structure of it.
However, theoretically, it should works. Just take note that there are total of 3 wire connected from the battery to the motherboard. Other than the +ve and -ve wire, the 3rd wire should be connection for the temperature sensor of the battery for the system to know that the battery is working well. If you are to remove the original battery and replace it with another one, need to make sure that the replacement battery also comes with this 3rd line, and its compatible with the motherboard.
This is a great mod I do have some ideas to make it better.
1. Use a higher capacity Galaxy S5 battery based off what I’ve seen those can go up to 4300 MAH meaning 1285 + 4300 = 5585 MAH which not only reaches the target you were hoping for but surpasses it.
2. Samsung has released a new NW-300 Walkman Series bringing 10 hours more of battery life I’m sure once the replacement batteries get made for this series you can easily put it into a NW-100 Series device and gain a lot more battery life. I have no idea what the MAH is and I can’t find it anywhere online but I’d say it would be around 1800 MAH instead of 1285 MAH.
3. Another way to improve battery life is removing a lot of bloatware on the device such as many android apps that you wouldn’t ever use making the Walkman use even less battery which overall improves battery life.
I hope this helps if you want even more battery life because you wouldn’t even have to charge this thing twice a week only once.
1. definitely the bigger the better, but need to consider how thick the overall result will be. I think best to find a balance in between.
2. I think you meant Sony. Yes, I do think the battery from A306 should be directly compatible with A105, do comment if anyone did this mod.
3. Agree, turning off the WiFi especially improve the battery life.
Hello did you get the dimensions of the a105 battery?
Sorry that I do not have the dimension. Never measure it while I am modding my A105.
Thanks for this mod instructions. My original A105 battery died completely. With your instructions I replaced the battery completely. I cut the battery wires from the original battery and connected a new bigger battery to those. I left the white wire not connected since there was only 2 wires coming from the new battery. I noticed after the replacement that in the UI battery charge stays at 60% no matter how long I charge it. Not sure why. Do you?
Hi, thank you for reading my blog. I believe the main issue with your problem is due to the 3rd wire from the battery. Normally the 3rd wire is for the temperature reading of the battery as protection of overheating. Without the 3rd wire, the system might detected this error and prevent the battery from charging. Some info about the 3rd wire that might be useful: https://www.reddit.com/r/diyelectronics/comments/wcy6jd/37v_liion_polymer_900mah_what_is_the_3rd_wire_for/
Some mentioned that they can hack the battery by adding resistance to the battery to give the 3rd wire, but I am really not sure on how the result will be.
Oh damn. Now thinking if I place the old battery inside with the white wire connected and route the red and black to the new one. Or do I then also need to attach these 2 batteries as you did?
Hi, I am really not sure which advise to give. But there are few options for your consideration, I think the white wire is a must for the charging to work properly so your options probably are:
– you can use back the old battery to have the white wire, and route the red and black wire to the old battery, this way capacity should be bigger and charging should works, but you will have a piggy back battery on the DAP
– I think you can get replacement battery from Aliexpress thats designed for Sony NW-A105, for example: https://www.aliexpress.com/item/1005005841202767.html, but beware that the capacity is not as it claimed. For this item, I have ordered, and from my initial testing the capacity is only around 1000mAh.
Hey, do you know which wire gauge you used for the wires on the second battery? If not, do you have any that you recommend?
What wire gauge did you use?
Hello, excellent work and proposal, I have a question, I have an original Sony spare battery identical to the one in the a105, can they also be put together? I tried the mod, but if I put the temperature cable together, the battery drops more and when I remove it, the device does not detect the second battery, what could I do? Or is a different battery necessary? Thanks for your answer.
Hi Dolphin4k, thank you for reading my blog. I am not sure the effect of connecting the 2 temperature signal together, I will suggest to connect only one temperature cable to the PCB Board, and you can wrap the other one with a wire tape to avoid any short circuit.
What do you meant by the battery does not detect the second battery? By right after connecting the +ve and -ve terminal of both battery together, A105 will not see them as 2 battery, it is still one battery to A105 but the capacity got bigger.