[BBguru64]

I recently upgraded a bunch of devices including phones and PC and ran into some very strange battery life and charging problems(Lesson #1 - change only one item at a time!). I wanted to share them here to help others that have faced similar issues

I was using the blackberry 9700 and found the battery life to be less than a day. I know I need to charge daily but 4-5 hours seemed really short. Well after a few days of running some experiments, I realized that my PC was set to go into standby in about an hour. When the PC goes into standby, the USB power was present but I guess the PC "brains" were shut down so charging also stopped. So while my BB was plugged in the battery charging supposedly overnight, it actually stopped after an hour.
LESSON - Sometimes short battery life is more due to the charging source rather than the phones performance. Make sure that your source like the PC or wall adapter is "awake" when charging

Next issue was charging a completely dead battery. After a really long day, my BB battery went completely dead. I tried charging it from the PC but it just would not do it. Finally I was able to charge only after I plugged into the wall socket. Now here is what I found - turns out that sound you hear when you 1st plugin the device into the PC is not just for your entertainment . When it does this, the BB actually tells the PC that it is there and ready to charge. But in order to do that the battery needs to have some life in it. Without this little juice, the PC cannot recognize that the BB is there and so it does not charge.
LESSON - Have some charge left in the BB if you expect to charge from the PC USB port. If the battery is completely dead, you need to have your wall adapter in order to charge.

I hope that this information was helpful.....at the very least it will help people who have seen similar issues and may blame the phone. Some of the conclusions that I have reached were with the help of the the kind folks at RIM and with the help of a buddy of mine who designs circuits into the Blackberry phones...

[aiharkness]

Wirelessly posted

Yep. First part is true all the way. Well known, or mostly well known, that laptops and netbooks shut down usb under certain circumstances, such as standby.

Second part is yes and no, or not always. My old desktop will charge a blackberry with a flat empty battery. The thing is, you will see the battery error icon until the battery takes on enough charge. At that point, you can do a battery pull and the device will boot. But it will typically charger faster on a wall charger, which makes a significant difference when the battery is very low.

[BBguru64]

Yes that is an interesting point and I should have been more specific (sorry). The battery error says that it is not FAST charging. Rather it is trickle charging untill it gets enough power to communicate with the pc and then start fast charge. Same thing happens on an IPOD (dare I mention on this site?). Difference is that on that device, the symbol shows that it is slow charging.

On the whole this process will take longer than a wall adapter. Most people will see that error and probably say it is an error and connect to the wall.

[aiharkness]

Wirelessly posted

I'm not familiar with an indicator of fast versus trickle. By my memory what I see is the no battery/dead battery icon, which in my memory is the same symbol for either case. The last time I went through it was with my old 8700g running 4.5. I haven't run the battery flat on the 9700.

Also, at least with the 8700, the desktop computer will sound when blackberry is connected to usb, even with the battery so flat the device can't boot.

Maybe things are different with new models and new device software. I don't know, so can't confirm or argue the point.

[mikeytunes@yahoo.com.sg]

This is a great point BBguru. Your point about the PC going into standby actually applies to most devices including Apple, Blackberry, Samsung etc. Most people do not realize that the lower battery life they get in phones is actually due to the source (i.e. PC) going into standby.

Regarding the earlier comment about trickle charge...again I am no expert here....but from what I understand, when the phone shows a dead battery symbol it is not really charging....But batteries in general do tend to collect some trickle charge....after some time in this trickle charge mode it starts the full charge but this does take a long time..

On my ipod for e.g. when there is a dead battery and you plug into a PC the battery symbol is red...it is charging but very slowly. After a few minutes of this...the symbol changes to green and then fast charge has started and the guage moves more quickly.

All you experts..please correct if something i said is untrue or confusing...

cheers

[aiharkness]

Wirelessly posted

As I reacall, if you begin with a booted blackberry and let the battery run down, the battery level indicator will turn yellow first when remaining battery life is getting very low, and then red.

When you begin with an unbooted blackberry with a battery that is too low for the device to power on and you connect to a charger (either USB or wall charger) the display will come on with the battery error symbol. But doing alt-caps-del or removing and replacing the battery will not boot the device initially, and not until the battery has taken on some threshold charge. I have no idea how many amps are deing drawn at that point versus later on as as the battery is charging.

You can't see the battery remaing charge indicator until you are able to boot the device. I would be surprised if the color of the icon reflects anything other than the remainging charge on the battery. If anything, I would expect the number of amps drawn to be max at that point and then drop to a trickle when the battery approaches full charge level.

[mikeytunes@yahoo.com.sg]

Perhaps I can help....I used to design battery charging circuits so have a little knowledge....When the battery is completely dead, it is not good to pour maximum charge into it (think a completely dehydrated person taking sips slowly to start).

So Ira you are partially correct but the full current and final tapering down stages are 2 and 3. Stage 1 appears when the battery is completely dead and usually this is a trickle charge to get some life into it.

Hope this helps..

[mikeytunes@yahoo.com.sg]

Oh and also regarding the signal on the device. I cannot be sure for all devices but the 2 devices I have operate differently.

For the ipod on a dead battery, the starting RED charging symbol tells me trickle charge. Then when it turns to a green color it tells me that fast charge has begun.

But my Blackberry cannot connect to the PC when it has a dead battery and so does not see to be able to charge at all. I suspect that this BB cannot charge from a PC on a dead battery but I cannot say that for all BBs.

thanks

[mikeytunes@yahoo.com.sg]

BBGURU64 - I have to correct you on one fact that you stated below:

LESSON - Have some charge left in the BB if you expect to charge from the PC USB port. If the battery is completely dead, you need to have your wall adapter in order to charge.

This is actually not true. Now I agree that with the standard USB cable which comes with the Blackberry that it is true. However there are a few cables out there that can charge a dead battery.

Sorry - feel bad about correcting anyone with the name GURU

[aiharkness]

Wirelessly posted

I have an 8700g that I keep as backup. I try to keep it charged but forget. I frequently let the battery run down to the degree that the device will not turn on. I charge it on an old HP desktop using the blackberry OEM usb cable. No problem. Except, as I say, one cannot boot the blackberry until it has charged for a little while.

[BBguru64]

I checked with a friend who designs these gizmos and here is his take on this. Now all the various results we are seeing from various people are all making sense

So as we have concluded, how you charge a dead battery really depends on which model of blackberry you are using. On some models of BB, if you have a dead battery it will not charge from a PC AT ALL but will from a wall socket.

On the newer models, the PC will charge a dead battery but much more slowly. It has to first get the battery to a level where the charging circuit can recognize it and begin charging. So while a wall adapter is still better the PC will work.

I had also requested on another forum if someone (ADMINS?) has a csquid cable that was talked about by some other users, if they can do an informal review that would be helpful.

thanks