Hi all, I've been having a problem with my iPhone 3gs, and I am wondering if I may have overdischarged the battery.
Basically I was using the phone while it was low on battery, and instead of shutting itself down at around 4% battery life it held out till 1% before shutting down. Since then I have not been able to charge it (tried cleaning the socket, different cables etc).
I had thought it may have been the docking port that was broken, but considering the circumstances I had a look at the battery.
I've attached a diagram containing the 4 connectors on the battery. The voltages I measured are:
A-B: 2.16V
A-C and A-D: 0.17 V
C-D: 0V
C-B and D-B: 1.95V
Id guess that A and B are the main power contacts, with C and D performing other functions (https://discussions.apple.com/thread/2744613?start=0&tstart=0). The fact that Im only getting 2.16V is a bit worrying (making me think Ive over discharged the battery).
According to here (http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries) the battery may have shut itself down (so wont be recharged), but it could be saved as the voltage is above 1.5V.
My main questions are:
Do any of you have any input on my diagnosis?
And any ideas how I would go about recharging the battery? I dont have a charger, but I do have various electronics bits and a microcontroller, so might be able to cobble something together if I knew what to make.
If it makes much difference, the battery is a Lithium-ion polymer battery (3.7V, 4.51Whr).
Thanks!
Basically I was using the phone while it was low on battery, and instead of shutting itself down at around 4% battery life it held out till 1% before shutting down. Since then I have not been able to charge it (tried cleaning the socket, different cables etc).
I had thought it may have been the docking port that was broken, but considering the circumstances I had a look at the battery.
I've attached a diagram containing the 4 connectors on the battery. The voltages I measured are:
A-B: 2.16V
A-C and A-D: 0.17 V
C-D: 0V
C-B and D-B: 1.95V
Id guess that A and B are the main power contacts, with C and D performing other functions (https://discussions.apple.com/thread/2744613?start=0&tstart=0). The fact that Im only getting 2.16V is a bit worrying (making me think Ive over discharged the battery).
According to here (http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries) the battery may have shut itself down (so wont be recharged), but it could be saved as the voltage is above 1.5V.
My main questions are:
Do any of you have any input on my diagnosis?
And any ideas how I would go about recharging the battery? I dont have a charger, but I do have various electronics bits and a microcontroller, so might be able to cobble something together if I knew what to make.
If it makes much difference, the battery is a Lithium-ion polymer battery (3.7V, 4.51Whr).
Thanks!
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