Battery, how does it charge ?


PowerGod

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Speaking with a friend yesterday I found some empty points in my knowledge about how charging works...


I know that charging is software controlled, so the OS must be active, and there's a security flag to prevent overcharge, but, how can happen if for some reason the OS will freeze while charging ? (A situation where you need to hard-reboot)


Does the battery will continue to receive power, forever ? Or without software instructions the charging will stop ?
 
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I'm fairly certain you would know that your pandora is not responding before you plug it in to charge. If you plug it in while it still works, and then leave it, there is no reason why it would be unresponsive during the charge. As for fail safes against that sort of thing, I don't know.
 
On the subject of charging... How detrimental is it the leave your Pandora plugged in permanently... Much the same as a house-bound laptop?


Is it better to take the battery out if you're going to do this? But then you have the risk of losing data if there's a power outage...


Sent from my HTC Sensation Z710e using Tapatalk
 
There's a chip that controls charging.


You can charge while not in a OS, but it will be slow charge.


Have no idea about crash.

On the subject of charging... How detrimental is it the leave your Pandora plugged in permanently... Much the same as a house-bound laptop?


Is it better to take the battery out if you're going to do this? But then you have the risk of losing data if there's a power outage...

Not anymore with WizardStan's tweaks.


It avoids a permanent charge.
 
But is this only with the Super Zaxxon? I'm on Hotfix 7 alpha 3. Waiting till all the kinks are ironed out before i upgrade...


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There's a chip that controls charging.

So the chip has a firmware by itself, right ? and WizardStan's tweaks are in that firmware ? I was thinking it was the kernel or some OS driver that manages the charge
 
But is this only with the Super Zaxxon? I'm on Hotfix 7 alpha 3. Waiting till all the kinks are ironed out before i upgrade...


Sent from my HTC Sensation Z710e using Tapatalk
I don't remember exactly which one, but the last battery fix occured prior to Super Zaxxon.

There's a chip that controls charging.

So the chip has a firmware by itself, right ? and WizardStan's tweaks are in that firmware ? I was thinking it was the kernel or some OS driver that manages the charge
Mmm i think the chip's advanced functions like fast charge are managed through the OS.
 
I think he is wondering if the charge chip itself has a fail safe that will stop charging the battery in case the charging script in the OS fails. Overcharging a LiPo battery is a very dangerous thing.
 
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No failsafe, the chip itself charges all the time. So WizardStan wrote his soft which prevents the overcharging.
 
The charge chip doesn't have enough brains to keep the battery at a consistent level. In theory it can charge the battery all on its own and then stop charging when it is full, but it fumbles the measurement and has difficulty restarting the charge until the battery is too low. It uses voltage to gauge how full the battery is, which isn't as accurate as you might think, and changing the current draw can affect the voltage in ways that confuse the chip into thinking the battery is more or less charged than it actually is.


Super Secret: with the right configuring, I was able to make it charge the battery while the Pandora was off, against everything I've said before, but there's no indication that it is or is not charging, and the window that tells the charge chip to stop working is so small some Pandora's (due to minor fluctuation in the board, possibly because they were sitting around unpopulated for months. I'm looking at you, CC <_< ) simply cannot reach it, so they would keep charging forever and you'd never know until the battery exploded; or the window is so wide that it stops charging well before the battery is full leading to people wondering why, after charging "all night", it's only at 85%. I've started investigating a few charge chips with more smarts in them. When the time comes I'm going to suggest something for the Pandora 2, assuming MWeston doesn't already have some in mind. In the meantime, the safest thing for the battery is software control.
 
^ So you think we'll have a different battery for the P2? I was kinda hoping the batteries would be interchangeable between the P1 and P2.


I was even hoping there would be the possibility of a higher capacity battery for the P1. ;)


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^ So you think we'll have a different battery for the P2? I was kinda hoping the batteries would be interchangeable between the P1 and P2.


I was even hoping there would be the possibility of a higher capacity battery for the P1. ;)

I think its a battery control chip on the main PCB , not in the battery.
 
I don't remember exactly which one, but the last battery fix occured prior to Super Zaxxon.
Don't quote me on this, but I'm pretty sure that it went into Hotfix 6, unless there's another fix that I missed.
 
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^ So you think we'll have a different battery for the P2? I was kinda hoping the batteries would be interchangeable between the P1 and P2.


I was even hoping there would be the possibility of a higher capacity battery for the P1. ;)


Sent from my HTC Sensation Z710e using Tapatalk

I would actually prefer a LiFePO4 battery for the P2, they can take more abuse but store a little bit less energy when new. However, LiFePO4 batteries will store more energy in the long run.
 
Well even if software crashes and chip fails to stop charging, the chip still manages to limit current going into battery enough to prevent it from leaking or exploding. We had some people here overcharging their batteries for a few months on early firmwares (before software control was added; I think they were Exophase and zodttd) and all they got is a puffed battery. I think I've read somewhere that the battery itself has some sort of protection too that prevents extreme discharge or overcharge.
 
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Thanks to all, I have the answer.


In case of OS freeze during the charging there's (again) a puffy battery risk.


So better not to leave the Pandora for so many days alone with strange daemons running, if used as a server of some type. (Or at least it's better to leave it without the battery inserted)


Or maybe leave it pinging some address at intervals (12 hours ?)... if the ping stop, there's a problem
 
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So better not to leave the Pandora for so many days alone with strange daemons running, if used as a server of some type. (Or at least it's better to leave it without the battery inserted)
It's fine to charge for a few days at least, possibly even a few weeks. I can't imagine someone doing something to cause the entire system to segfault and not noticing for weeks. Seriously, it's so unbelievably unlikely to just up and stop without any intervention that I wouldn't even think about it. It's possible it could crash while it is in use, but if that happens then I'm hoping you're aware that it happened :p
 
So better not to leave the Pandora for so many days alone with strange daemons running, if used as a server of some type. (Or at least it's better to leave it without the battery inserted)
It's fine to charge for a few days at least, possibly even a few weeks. I can't imagine someone doing something to cause the entire system to segfault and not noticing for weeks. Seriously, it's so unbelievably unlikely to just up and stop without any intervention that I wouldn't even think about it. It's possible it could crash while it is in use, but if that happens then I'm hoping you're aware that it happened :p

I think like you ;)


But the friend of mine is always thinking how to use EVERYTHING as a server (even a carrot if you enter in the argument)... he is just happy when something do something and you don't have to touch it anymore... so when I started the Pandora argument I was filled with security questions...


Anyway who knows what someone wants to do with this hardware... when I started to look at this project it was "for gamers only", but after some years I see any sort of use for it
 
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