Success! DIY Battery Replacement for D2

[dxps26]

Disclaimer: The following text and images are for illustrative purposes, and following the instructions therein will be at your own risk.

Evening, Folks.
After 2 years of heavy use and abuse, My D2 was finally giving up. The battery was getting hotter during use with each passing day, and one day, I noticed that one corner of the D2's back was bulging out, pushing the rear case open by a few millimetres. this gap grew larger over the course of the next few days, and although the D2 was soldiering on like a Champ, without complaint, I thought it would be wise to leave it be, until i found out what the Issue was. A Quick look in these forums confirmed that it was battery leakage, and looking for spare batteries gave me the option of mailing the D2 to Korea@the cost of about $80, or Going the DIY way.
Someone on Anythingbutipod had already done the homework - a thread about replacement batteries mentioned the Nokia BP-4L battery pack, which seemed to be a perfect fit for the D2's battery area. Luckily, I own a Nokia Eseries E63, which uses the same battery. I tried to fit the Nokia battery in the D2, after opening it up, and it fit like a glove.


This is the state my battery was found in, swelling up from one corner. the copper foil felt like there was some liquid behind...thankfully, the package was intact, and there was no spillage onto the D2's innards.

Next step was to buy a BP-4L battery, which cost me the equivalent of $46. Some Knockoffs can be had for as low as $18, but Genuine Nokia Batteries are VERY reliable, last long and not leak, swell, or explode. The BP-4L is particularly expensive, because it is found in the ESeries and some NSeries phones, that represent the top-end line of Nokia. Nonetheless, the battery is indeed the _best_ phone battery out there. I then had to remove the wiring from the D2's battery using a Soldering Iron. The Leads were then soldered onto the Contacts of the Nokia Battery, and sealed with a drop of Epoxy. Note that the contacts are Very small, and your regular Soldering Iron will not do. You need to use one with a very fine tip, commonly used for Cellphone and electronics repair. Do not use any liquid/Rosin/wax for the solder, as it might penetrate the battery and cause problems.

The battery was then seated into the back cover. The default battery pack is wider, but just as thick and long as the Nokia BP-4L. this leaves a gap on both sides, but the back cover has some sort of double-sided tape stuck on it to keep the original battery in place, and the replacement battery will usually catch on to that. Otherwise, you could use the sort of double-sided tape used by photo-framers, which is very thin and holds well.


The Acid test was to test the charging, and it worked fine! I used the OEM Battery from my 3-month old E63, and gave the phone a new Battery (less Risk, i guessed)
This battery was at about 80% charge and it showed up as 3 bars on the battery indicator.

The Casing now closes up completely, without any gaps or cracks.

Project finished! The Player is functioning normally as I type this, and the overheating I mentioned is absent. Next Step will be to benchmark battery performance.

Notes-The BP-4L is a 3.7V, 1500 mAh battery, 100 mAh less than the OEM battery. this will obviously mean a lower playback time, but as everybody knows, all batteries lose capacity over time, affecting playback time. So this hack might not give you the much-vaunted 52 hour playback time, but something like 48-50 hours, which is still great. Moreover, Nokia Batteries go through stringent quality control, and they often do more than what it says on the box. Some websites are selling 1800 mAh replacement batteries for the D2, but they seem to be sourced from someplace like Shenzhen, home of the KIRF... so i'd trust a 1500 mAh Genuine Nokia Battery over some dubious 1800 mAh battery anyday. Just my Two cents.

Warning-Do not Attempt to remove the labels on the Nokia Battery. For that matter, don't even think about dissecting your old battery!

[Noobie]

Very good, thanks for sharing man!

[Levi_s32]

Wow,you did a good job..Now becouse of you anybody with battery problem with their D2 can replace them easily.Now can you do a battery test and let us now how much what play time you get ussing the Nokia 1500 mHa?thanks

[rubicon]

Oh siick. do a benchmark for us, cause this sounds pretty darn sweet to keep this little bugger going and going and going

[trouwedr]

Well done dude, this is really cool.

[paulr]

I've been wondering whether this might fit, especially if you remove the outer shell:

http://www.dealextreme.com/details.dx/sku.6426

Update: I don't think the above one will fit, but this one might: http://www.dealextreme.com/details.dx/sku.6440

[dxps26]

Originally Posted by paulr

I've been wondering whether this might fit, especially if you remove the outer shell:

http://www.dealextreme.com/details.dx/sku.6426

Paulr, I really don't think it's a good idea to remove the outer casing of any Lithium-Polymer/Li-ion battery. Plus, this battery seems to be seated into a sort of plastic casing that probably keeps all the nasty chemicals sealed inside...if the battery was somehow isolated from the casing, maybe then, but i'd suggest you avoid it.

on a side note, I showed the old D2 battery to an electronics guy near my place, and he said he could get the same battery for me at a lower price than the BP-4L. however, when I asked him about the brand, discharge rate etc. he was clueless.
Apparently, thee's a whole underground industry in China where they make your batteries 'to order' , slapping together individual cells in a crude package that is covered in genuine-looking stickers and sold as the real deal.

[paulr]

There are some places claiming to sell OEM D2 batteries--type the battery part number (I forget what it is but it's stamped on the old cell) into google and you should find some sources. It's good to know that the BP-4L works since that cell should stay available for a while. There are some much cheaper substitutes available for it, as you say. My own experience with low cost cellphone batteries is they don't work as well as the originals, but they are usable.

I really wish Cowon (or whoever) would make a G3-like player (i.e. monochrome display, no video playback, runs on a standard AA cell instead of lipo) but with more capacity and with an SD expansion slot like the D2.

[dxps26]

Originally Posted by paulr

There are some places claiming to sell OEM D2 batteries--type the battery part number (I forget what it is but it's stamped on the old cell) into google and you should find some sources. It's good to know that the BP-4L works since that cell should stay available for a while. There are some much cheaper substitutes available for it, as you say. My own experience with low cost cellphone batteries is they don't work as well as the originals, but they are usable.

Paul,
I looked for a part number, or any identification mark on the OEM battery. I could not find anything. The battery looks completely Custom-designed, but thankfully, it's an industry-standard 3.7 volt one

As far as availability of the BP-4L is concerned, there's no need to panic. You can get batteries for dinosaurs like the Nokia 3310 today, so i'd say the BP-4L will still be around when our D2's finally kick the bucket

Like I said, i'd rather trust a good phone battery over some 'brand X' battery...my battery guy showed me a fake BP-4L alongside the genuine article... you'd be surprised how far down into the details these counterfeiters get, right down to the holograms, the serial markings, etc. Not surprisingly, the fake battery was already showing a slight bulge!

[dxps26]

Okay, here is the test environment that I will set up for the D2, Post-Battery-Replacement. Let me know if the conditions are adequate for an accurate result-

Battery Status-Run player until battery meter statrs blinking, and charge with the supplied wall wart charger until the screen shows the 'battery full' screen.

Volume and earpieces-Volume set at 25, and standard OEM earphones connected.

Effects-All effects are turned off.

Temperature-the player stays within a 28-35 degree celsius range (I cannot help this. it gets really hot over here these days, and I will need to carry the player around all day to check the status)

Playlist-for this test, I selected a folder filled with random songs from recent Bollywood hits such as DevD and Delhi-6...not at all my usual selection, but these are the only 128 kbps Mp3 files I have. Everything else is either 320k Mp3 or FLAC. (on a side note, don't know what is it with the rest of the world and that silly song from Slumdog millionaire... DevD's music is better.)

AmIdoinitrite???

[rapide_23]

Just found this on ebay: http://cgi.ebay.com.au/Replacement-f...d=p4634.c0.m14

[cowai]

Why test with 128k?
I think the majority here listens to 192k or higher. I only use 320k...

[vampire666]

Originally Posted by cowai

Why test with 128k?
I think the majority here listens to 192k or higher. I only use 320k...

He wants (and should) test with 128k mp3 because the 52hours Cowon stated is while playing 128k mp3.
He is trying to recreate the same testing method Cowon had, so we can have an accurate test.

[dxps26]

All right, the Results are in- With the above mentioned test conditions, I get a total playback time of 34 hours, give or take an hour or two. i recently discovered that there was a medium-quality VBR file in my playlist, and that may be influencing the results. but by my guess, a 40-hour playtime is within target, given that you use a fresh battery, and the ambient temperature is low. My own battery was 3-4 months old, so it would have lost capacity from the original 1500 mAh.

I'm still very satisfied with the results though. you can't expect Factory-fresh performance from a DIY hack job.

I will do this again with a single 128k test track on endless loop, keeping the player at room temperature. But, as anybody here can attest, it's hard for us aficionados to get away from our D2's!!! )

[paulr]

34 hours sounds pretty good, especially since the Nokia battery is physically smaller than the Cowon battery, both in width and in thickness (because of the plastic shell).

Mugen Power (mugenpowerbatteries.com) is supposed to be a pretty good manufacturer, and they have a thicker BP-4L replacement with supposedly 3600 mah. It comes with a replacement cover for the E71 phone or N810 PDA to accomodate the extra thickness. It probably won't fit in the D2 even if the shell is removed though. They also have a normal thickness BP-4L replacement that they claim 1800 mah for, though I can understand wanting to stay with Nokia.

I'm not sure what the issues are with removing the shells of lipo batteries. I've done it with li ion Kyocera phone batteries and it's no big deal. The Kyocera batteries have gotten hard to find, but it looks possible to refurbish them by putting some smaller battery into the shell.

A Nokia BP-4L from Nokia USA is around 65 USD, ouch!! Some other stores sell them for less, but I have no idea how to tell if they are selling fakes.