Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

$47.94 for 3 packs of 2 ($15.98 per pack). A definite bargain, especially compared to the Mugen.

I forgot to mention, when I ordered my Mugen covers they had a notice stating they were giving 5% of all sales to the Japanese Red Cross, so if anyone was thinkng about ordering from Mugen, why not do it now.

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

It has not arrived yet... hopefully next week


So i assume that the total price comes to 68$ with covers.....
Again for everybody here, 'retsaw' is going to get 2x _better then mugen battery's_ + 2x _single better then any current tested battery_ with the option to go dual on both N900 or mix and match.

FOR 68$....

I know that many don't want to fiddle around with battery's to make their own battery, but if you know someone that is mildly experienced with a soldering iron then this i worth the consideration.

And a note on durability, have made 4x mods so far with better and better battery's, and every one of them are still fine, 1 mod is still being used to power the led flashlight, 2 mod is being used by 'redkarma', 3 mod is in the process of being sold to fellow maemo member, 4 mod is F**KING rocking away in my N900.

And i am sorry that i don't have the time to make some battery's for you out there since there has been some requests.

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

Hi dr_frost_dk,
I'm really glad you're doing all that and giving us all that sweet info!

And I'm looking forward some advice about making my own battery. My main concerns are these:

Knowing that these batteries are REALLY DANGEROUS, so:

1)How cautious should I be while taking apart the top part of the battery? I mean, how far is it safe for instance to poke a hole in it? Half millimeter? I mean, I will have to tear apart some of its protecting thing because I guess that the top(where the contacts are) should be glued with the Battery, so I'll have to remove part of the protection of the battery alongside with the top, so... a bit of description on it?

2)How hot the solder can be while working ON the battery? Can you extend on that?

3)In order to reduce the danger, I was planning to work on them while flat, or almost flat. But then I was thinking that it could produce some problems while charging in the case of the batteries not being _exaclty_ equal, and etc. What would be your advice here?

Thank you!

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

First of all, it is not that dangerous, doing my mods i short the battery several times (under a second) because i sometimes get impatient

im guessing that this will be the scud battery's?, but the way i do this is the same with all battery's are to cut away 3-4 mm of the tape/cover (label with text...) so that the plastic top is more exposed and not taped down, now i just wiggle the top until it lets go from the battery, it is still hanging on with the wires, then i pull the top as far up as i can, and again wiggle it from side to side until the wire/flat cable brakes off, this leaves a bit of flat cable/wire on the + & -, now i solder on these pads, here it is important to do i kinda quick, not heating up the battery to much, the - is the easy one, it is the one sitting alone and is not connected to much inside the battery, so this heats up quick, the + on the other hand needs some heat before the solder will hang on.
NOTE: i have not yet been able to ruin one battery by to much heat on either + or -, i also set my soldering iron to high temperature like 400C

No need to discharge the battery's, if they where really discharged to under 3.6v and where shorted for sometime this will actually kill them verses charged to 4.2v, every time i do this my battery's are charged fully up.

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

Have just updated Post #2 with pictures of the dual scud, dissemble of battery & schematic

so 'Temporal' for additional info look to post #2

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

Why should this be impossible? I've most likely the same capacity in some of my rechargable AA (Mignon) batteries?

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

WOW, we have been over the hole comparing AA, A, C, D battery's to Li-ion/LiPo many times

And im pretty sure that AA doesn't have a capacity of over 2000mAh, thats A battery territory
Scratch that, just checked... has happened a lot since i last looked at AA battery's.

And remember AA, A etc are 1.2V and Li-ion are 3.7V this means:
1.2V - 2250mAh AA/A battery = 2,7Wh
3.7V - 2250mAh Li-ion battery = 8,3Wh
So this means that you need 3x AA battery's to have approx the same capacity of one Li-ion

And all my testing so far has shown a max limit of approx 1500mAh for the BL-5J size

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

dr_frost_dk,

Really really thank you! This last bit of info was what I needed to get over my fear and start the modding. You was right, I'm waiting for the scuds.

Again, thank you!

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

How are the dissemble photo's are they easy enough to follow?
Feedback will help make better guide.

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A
 

what you may want to add to the schematic is the breakout point for the 2mm charger.

I'm still waiting for my mugen cover and for the japod batteries. But I can say that I am very impressed with the batteries I'm running. They appear to last longer than the genuine nokia battery. Occasional web browsing, 3g, online for aim / msn / facebook / skype. These batteries average about 15 hours, the genuine nokia battery about 13 hours.

I have an idea for a mod that I will implement when my mugen cover arrives. With your current setup and the batteries being hard-connected to the mugen backcover, what I'm hoping there will be space to do is have a computer fan connector to be used to detach the batteries from the 2mm connection. Means you can swap batteries easily, whilst still using the external charger