A tale of three smartphones: Rescuing a dead battery
Published by Steve Litchfield at 10:11 UTC, July 2nd 2009
Faced with a dead Nokia N86 that refused to charge, Steve Litchfield didn't panic - armed with the luxury of some of other devices to hand, he was able to get the N86 and its battery revived and working properly. And, in the process, learned that all Nokia's batteries are electrically interchangeable. Maybe these concepts will save the day when your precious S60 phone appears to have died?
Early Nokia firmwares are buggy - that's a given, in my experience - and the N86's is no different. I awoke this morning to a phone that appeared dead. Some rogue OS process or S60 application had been running away with the processor during the night and some bug in the firmware hadn't protected the battery by closing the phone down when the voltage got low.
The result was that, even after taking out the battery for a minute (to let any remnant charge leak out of the electronics, that might be confusing the logic in the circuitry) and then reinserting and plugging in the mains charger, did no good - no Nokia logo, no charging animation - nothing.
First reaction: panic. Was the phone itself dead? Was the battery irretrievably damaged?
Second reaction: I'm fortunate to have other devices around, I wonder if any of them can help.
Now, the N86 uses the BL-5K battery, common only to itself and the N85, but I couldn't help noticing that the pin formation on all my Nokia batteries looked identical. Somewhat tentatively, I inserted a fully charged BL-5F battery from my N95 into the N86's battery bay. It just fitted 'vertically', although it didn't use all the available width. Press the power button and instant life - the N86 booted fine.

Proving that the phone itself was largely OK, which was a relief. But what about the BL-5K battery? I wonder if the electronics in a different device (perhaps of an older, more electrically robust generation) could charge it where the N86 couldn't? I couldn't charge it in my N95 since the battery bay was too narrow. Cue a hunt through my admittedly larger-than-usual device cupboard.
I found my old Nokia E90, with the largest battery bay of any device, designed for the huge BP-4L. Again the pin connectors matched in formation and general position though, so I rested the BL-5K up against the contacts and inserted my charger. A beep and the battery appeared to be charging normally!

Had I saved the battery? I'd been worried that the charge had been taken so low that it wouldn't now work at all. But it seemed to be accepting charge again. An hour later, I took the battery out and put it back into the N86 8MP. Now came the moment of truth. Had the battery actually been charging and would the N86 accept it again and finish the charging process?

Yes!
So, things learned from this early morning panic and rescue mission:
- Batteries from one Nokia phone often fit (at least electrically, for diagnostic purposes) other phones
- Just because the electronics in one phone won't charge a battery doesn't mean that the electronics in other phone won't.
Steve Litchfield, All About Symbian, 2 July 2009
Categories: How To, Comment, Hardware
Platforms: General
Feature Discussion
pintofale
I've noticed that very dead phones don't light up with the 'Nokia' logo for five minutes or so (perhaps longer) after they go on charge - perhaps you should have left the N86 plugged in and gone off to mash up?
carrotmadman6
One more thing to learn - even though the device doesn't boot up, the battery is being charged.
Unregistered
I remember a couple of years ago when my friend tried my battery in his phone. His phone was a Nokia 6510 and my battery from a Nokia 6610. The battery fitted physically perfectly but not electrically. His phone never booted again until back from the Nokia Service Centre, so battery exchange is not always as successful as in Steves case.
zyler
You should add a disclaimer to this post. This is probably not the kind of thing Nokia would approve of.
Unregistered
nicely done steve!
this taught me a lot! glad to see that u can actually fit one model's battery into another
slitchfield
@carrot and pintofale: Come on, give me some credit. The FIRST thing I did was try leaving the mains charger plugged in and waiting for the device to come to life. I figured that after 15 minutes it wasn't going to, hence using a different device as battery host 8-)
icebox
Even if they fit and even if the voltage is the same the charging logic EXPECTS a certain capacity : i.e. amps. And it charges with a certain speed according to that capacity and temperature. So there's also the possibility to blow a small battery in a phone calibrated for a bigger one, or the temperature sensors inside the batteries speak different languages.
I sure wouldn't want to try it unless forced in an emergency. Li-ion batteries tend to ruin the fun when not charged properly
oecboy
old nokia phones didn't use to work with exchanged batteries. Had tried unsuccessfully with my n-gage qd once. Newer one's do work. Even if the battery doesn't fit verically in the other phone, i have charged it while keeping it pressed into its position with my hand
Cdx
In the middle east lets just say we have varying current and voltages :) I have learnt NOT to let my n85 go completely flat. If it does then sometimes only a true 240v supply will bring it back on line. This does not apply to my n70 so maybe these newer batteries have an issue ?
shadamehr
I concur with the first post...
I have OFTEN had very dead batteries that don't do ANYTHING in terms of appearing to charge, and giving the tell tale beep, until sometimes after five, and even TEN MINUTES, of being connected to the charger.
PLEASE ALL (and Steve) bear this in mind before risking any potential electric shock, or device damage, swapping batteries around...?
stuclark
I'm surprised this hasn't been mentioned in relation to this article, but... this is a generic trait of phones that use USB derived charging sockets!
I had this explained to me once accurately from someone who knew (and worked at the time for a major phone manufacturer) - essentially though, when using USB to charge, the phone needs a certain amount of power in the battery BEFORE it can even POST (boot in English) enough to turn the screen on.
The basic rule is, as people have said... leave the charger attached to the phone, EVEN IF it appears to be doing nothing - sometimes (Sendo & Motorola phones were bad for this, along with early HTC devices) they can take 30 minutes or MORE before they'll turn on!
Oh, and as far as this article goes - swapping batteries out is OK, IF and ONLY IF, the voltages are the same. Even then though, the currents may not match, so this should ONLY be done in an emergency!
TheUndertaker
dont limit it to nokia alone!
my ngage qd bl6c battery worked fine on my sony ericsson p910i! booted up and it even gives more battery capacity than the original p910i bst15! :D
slitchfield
Fair points guys. I only gave it 15 minutes or so, I think, before I gave up and went for the lateral thinking approach. If it happens again then yes, leave it longer.
Charging time is also long - it's taking five hours or so to fully charge this N86 from scratch. Ouch!
Rem
Be sure to check the battery voltage and current first. not all phone batteries are created equal.
I tried my sister's Nokia 7610 battery into my Nokia 6233 once as a geek experiment but didn't work. Glad it didn't toast the phone though. :)
Unregistered
Thats the camera bug. If the cam app is closed by the lens protector the power consumption of the device stays at 1W. Only if you close the cam app manually by clicking exit its ok...
Hardeep1singh
Reminds me of the good old days when I used to use BL-6C batteries in my 6600 and 6630 as it provided more battery life than BL-5C, but it didn't fit when I bought an N70 as BL-6C was thicker and I couldn't close the back cover.
It seems to me that this problem is caused by USB charging mechanism, it needs power to function.
nparayo
I have a question on chargers Lets take Nokia, Say I have a charger at 5V 800mA which is supplied with my Nokia phone A. Another charger 5V 400mA supplied with Nokia phone B. What is the harm in interchanging these chargers with the different phones?
Cdx
The above posts about usb charging would explain my problems with my n85 and why my n70 does not have the same issues.
Unregistered
Got the 6c battery to fit in my n70 but the because of the battery size the camera slide mech does not work :)
Unregistered
I've even managed to boot up a panasonic using a nokia bl5c battery. I found the econ thing on a bus but the battery was flat and i couldn't find a charger. The pins on the phone hardly lined up, but i kept them in place long enough for the phone to boot up. This makes of wonder if i could adapt a smaller battery to my old 3300 which uses a very old type of battery...
Unregistered
3 years back when I owned a Nokia 5500, with BL 4C battery with smaller pin charger, forgot the charger
I was charging its battery on my Mom's Nokia 1100 with BL 5C battery with the older and bigger charging pin.
Dude, you go to India, you cannot even imagine what people do with their Nokia phones
Unregistered
Really, what do they do ? Do they put them in their panties while vibrating ? You Indians.
22 Comments / Post New Comment