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I appreciate such softwares and possibilities, but I would not recommend using an old smartphone: continuously charging its battery represents a huge risk, hist

I appreciate such softwares and possibilities, but I would not recommend using an old smartphone: continuously charging its battery represents a huge risk, history just reminds us about battery explosion, detective cables, defective wall chargers. If you add also that batteries, when aging, are a real risk, then, thanks but no.

RL_Quine 7y ago
It’s really a non concern. Realistically if there was a problem it would present in normal usage when people are charging them in bed. The amount of superstition about lithium batteries is crazy, given how many of them are used in any household on a daily basis. The battery is functionally not being used if a phone is plugged in and the battery isn’t drained. This misinformation comes back from when people were using Nickel Cadmium cells decades ago, those cells were functionally continuously charged because it caused absolutely no harm to them.
- tjoff 7y ago
  Two major differences: The battery will be charged to 100% constantly. The battery will be much older and has worse capacity than most consider even usable.
  - officialjunk 7y ago
    remove the battery and leave it plugged in
    - NullPrefix 7y ago
      Would expect this to work only if by plugging in you mean plugging in 3.7V to where the battery's terminals were. Can't recall succeeding to boot an Android phone with USB charger and no battery.
      - gambiting 7y ago
        Nexus One works fine without a battery, but that's an absolutely ancient phone by any standard.
  - nitrogen 7y ago
    The battery also has a built-in charge controller to prevent overcharging, and if the capacity is significantly lower, shouldn't the risk of that stored energy being released also be lower since there's less energy stored?
    - RL_Quine 7y ago
      The phone has an on board charger. The battery itself has its own controller which will disconnect the battery from the charger if it goes over voltage, under voltage, or over temperature. The "percentage charge" of a lithium cell isn't really any measure of its safety. Even at 0% charge the cells can still auto ignite, there's an incredible amount of energy in them when they're considered to be empty.
    - sandos 7y ago
      The problem is lithium doesn't like being at 100% state of charge for prolonged periods of time. Normally you charge it up, then use the battery. When on a charger the voltage will sit close to fully charged voltage, and that ages the battery quickly. Add some heat and you may have a problem eventually. In my experience, its usually "only" a problem when later, you discharge the battery and then try charging it back up, thats when stuff starts burning.
  - RL_Quine 7y ago
    > The battery will be charged to 100% constantly. So? That's a non-statement as far as safety goes. It's as relevant as the color of my shirt, or the current date, or the state of the moon.
- danielh 7y ago
  The difference is that a phone might get hot when the camera is running 24/7 and CPU load is high, e.g. due to motion detection. To add some anecdata: I had an old iPhone (IIRC a 4s) running as security cam for about 6 weeks. When I returned, the case was cracked due to a swollen battery.
  - gambiting 7y ago
    ....and? I imagine the phone shut down and literally nothing happened? Batteries are kind of designed to do that in case of cell failure, actual fires are incredibly rare.
  - rmuratov 7y ago
    Care to elaborate your software setup?
- geggam 7y ago
  I have left old phones plugged in because I used them with wifi in the workshop. More than once I had to quit using a certain phone because the bulging battery started getting hot. Granted they were 5+ years old but its there.
tjoff 7y ago
If only batteries were still easily removable... I'm currently integrating (project is on pause but one day!) an android tablet into an old car. And the battery was a dealbreaker. So I've removed the battery and added an resistor to trick it into booting anyway. Only problem is that android think the battery is dead so it won't perform system updates unless I first charge it. Which I guess is fine in this case since the tablet is out of support anyway.
- cellular 7y ago
  I wish phones would work with no battery when plugged in. What resistor value, and where did you place the resistor to be able to boot without a battery?
  - tjoff 7y ago
    Don't remember, if you are lucky there are guides for this for your particular device. If I remember correctly there are four terminals, aside from power one of them might be battery temperature which I think is mandatory. I measured the resistance on the original and mimicked it. Basically hardcoding the temperature since I don't have a battery. But I could be very wrong on this. Google it first!
- winrid 7y ago
  You can get a $20 Android phone with a camera and removable battery nowadays.
  - yyyk 7y ago
    Camera, removable battery and X% chance of having a preinstalled rootkit (e.g. [0]). It's better to pay a bit more in order to have peace of mind. [0] https://arstechnica.com/information-technology/2016/11/powerful-backdoorrootkit-found-preinstalled-on-3-million-android-phones/ https://arstechnica.com/information-technology/2016/11/power...
    - mrandish 7y ago
vbezhenar 7y ago
May be there's market for fire-proof smartphone cases?
- xfitm3 7y ago
  You can buy a fireproof lipo charging bag today

RL_Quine 7y ago

It’s really a non concern. Realistically if there was a problem it would present in normal usage when people are charging them in bed. The amount of superstition about lithium batteries is crazy, given how many of them are used in any household on a daily basis. The battery is functionally not being used if a phone is plugged in and the battery isn’t drained. This misinformation comes back from when people were using Nickel Cadmium cells decades ago, those cells were functionally continuously charged because it caused absolutely no harm to them.

tjoff 7y ago
Two major differences: The battery will be charged to 100% constantly. The battery will be much older and has worse capacity than most consider even usable.
- officialjunk 7y ago
  remove the battery and leave it plugged in
  - NullPrefix 7y ago
    Would expect this to work only if by plugging in you mean plugging in 3.7V to where the battery's terminals were. Can't recall succeeding to boot an Android phone with USB charger and no battery.
    - gambiting 7y ago
      Nexus One works fine without a battery, but that's an absolutely ancient phone by any standard.
- nitrogen 7y ago
  The battery also has a built-in charge controller to prevent overcharging, and if the capacity is significantly lower, shouldn't the risk of that stored energy being released also be lower since there's less energy stored?
  - RL_Quine 7y ago
    The phone has an on board charger. The battery itself has its own controller which will disconnect the battery from the charger if it goes over voltage, under voltage, or over temperature. The "percentage charge" of a lithium cell isn't really any measure of its safety. Even at 0% charge the cells can still auto ignite, there's an incredible amount of energy in them when they're considered to be empty.
  - sandos 7y ago
    The problem is lithium doesn't like being at 100% state of charge for prolonged periods of time. Normally you charge it up, then use the battery. When on a charger the voltage will sit close to fully charged voltage, and that ages the battery quickly. Add some heat and you may have a problem eventually. In my experience, its usually "only" a problem when later, you discharge the battery and then try charging it back up, thats when stuff starts burning.
- RL_Quine 7y ago
  > The battery will be charged to 100% constantly. So? That's a non-statement as far as safety goes. It's as relevant as the color of my shirt, or the current date, or the state of the moon.
danielh 7y ago
The difference is that a phone might get hot when the camera is running 24/7 and CPU load is high, e.g. due to motion detection. To add some anecdata: I had an old iPhone (IIRC a 4s) running as security cam for about 6 weeks. When I returned, the case was cracked due to a swollen battery.
- gambiting 7y ago
  ....and? I imagine the phone shut down and literally nothing happened? Batteries are kind of designed to do that in case of cell failure, actual fires are incredibly rare.
- rmuratov 7y ago
  Care to elaborate your software setup?
geggam 7y ago
I have left old phones plugged in because I used them with wifi in the workshop. More than once I had to quit using a certain phone because the bulging battery started getting hot. Granted they were 5+ years old but its there.

tjoff 7y ago

If only batteries were still easily removable... I'm currently integrating (project is on pause but one day!) an android tablet into an old car. And the battery was a dealbreaker. So I've removed the battery and added an resistor to trick it into booting anyway. Only problem is that android think the battery is dead so it won't perform system updates unless I first charge it. Which I guess is fine in this case since the tablet is out of support anyway.

cellular 7y ago
I wish phones would work with no battery when plugged in. What resistor value, and where did you place the resistor to be able to boot without a battery?
- tjoff 7y ago
  Don't remember, if you are lucky there are guides for this for your particular device. If I remember correctly there are four terminals, aside from power one of them might be battery temperature which I think is mandatory. I measured the resistance on the original and mimicked it. Basically hardcoding the temperature since I don't have a battery. But I could be very wrong on this. Google it first!
winrid 7y ago
You can get a $20 Android phone with a camera and removable battery nowadays.
- yyyk 7y ago
  Camera, removable battery and X% chance of having a preinstalled rootkit (e.g. [0]). It's better to pay a bit more in order to have peace of mind. [0] https://arstechnica.com/information-technology/2016/11/powerful-backdoorrootkit-found-preinstalled-on-3-million-android-phones/ https://arstechnica.com/information-technology/2016/11/power...
  - mrandish 7y ago

vbezhenar 7y ago

May be there's market for fire-proof smartphone cases?

xfitm3 7y ago
You can buy a fireproof lipo charging bag today