Hey
As a possible solution to the low battery life of the G1, I bought a solar panel charger. (http://www.maplin.co.uk/Module.aspx?ModuleNo=229254) To test it, I went and sat in the sun for a while, with a multimeter. When charging an old Nokia, which has a 3.7v battery, the Nokia's battery was drawing about 200mA. Not a lot, but enough to extend the life of the battery if you're out on a walk.
However, when I plugged the solar panel into the G1 (also a 3.7v battery), it only drew 10-20mA. Now, presumably this is due to some sort of charging circuit in the G1. I know some battery chargers have a diode in to prevent back-flow, and they can have a hefty voltage drop on them. Perhaps the G1 has something similar.
My solution to this would be to have a separate connector that will fit between the G1s battery and the phone to supply current directly to the phone/battery. If the phone is using less current than the solar panel provides, presumably the battery will then charge. Otherwise, the phone will run off the solar panel & battery combined, meaning the battery will last longer. I'd not use the panel when the battery is full, so it wouldn't overcharge, and I would put a 10 ohm resistor in to make sure the charging current is fairly low.
Forgetting about the difficulty of creating the connections, does anyone know anything about the manner in which the G1 handles charging that might be damaged by what I'm proposing?
Why do you post in Development section? Becareful when you created new thread in a sub forum!
Thread Move to Dream accessories.
The battery is irrelevant, it's what the charging-circuitry takes as input that matters. (And, regular lithium-cells usually run at 3.7v, so there's no need to check that (Unless it's some special phosphate-based cell, or something fancy))
The G1 takes 5v.
If i recall correctly, Android handles the power-consumption of the charging circuitry when booted. I think it could be regulated from debugfs... But this is dangerous.
(imfloflo: If the above is true, this is indeed Android development...)
For the battery to charge, you need to supply a higher voltage, and i don't know the limits of the voltage-regulation in the device. This could potentially overload it, rendering the device useless (Unless you have the ability to solder smd components, and the regulator is not part of the SoC).
Also, DO NOT try to charge a lithium-based battery without the charging circuitry, you will end up overcharging/overheating it, and that's NOT something you want to happen (If you don't cool it fast enough after this has happened, it will explode, taking the phone, and whatever else is near (Your hand for example) with it.).
Joushou said:
DO NOT try to charge a lithium-based battery without the charging circuitry, you will end up overcharging/overheating it, and that's NOT something you want to happen (If you don't cool it fast enough after this has happened, it will explode, taking the phone, and whatever else is near (Your hand for example) with it.).
Click to expand...
Click to collapse
Most Li-Ion batteries have a small control circuit built in.. So unless you take the battery apart and try to charge the individual cells, that shouldn't be a problem.
After I broke the usb socket on my wizard, I used to charge the battery with a plain usb cable chopped down the middle with the wires taped onto the battery terminals.. never blew my hand off once.
Disclaimer: I take no responsibility for any damaged or destroyed limbs resulting from attempting idiotic things like this.
goldenarmZ said:
Most Li-Ion batteries have a small control circuit built in.. So unless you take the battery apart and try to charge the individual cells, that shouldn't be a problem.
After I broke the usb socket on my wizard, I used to charge the battery with a plain usb cable chopped down the middle with the wires taped onto the battery terminals.. never blew my hand off once.
Click to expand...
Click to collapse
Yeah, as dubious as those "clip" usb chargers are, I have not heard of anyone's Li-Ion or Li-Po cellphone battery violently venting as a result of charging past 4.1v. Generally with lithium-based cells, if they have been packaged into a battery then there is probably a basic protection circuit against overvolt, undervolt and shorts.
That said, I would still recommend charging through the mini-usb rather than trying to jury rig together some kind of interface to go between the battery and the contacts.
jashsu said:
Yeah, as dubious as those "clip" usb chargers are, I have not heard of anyone's Li-Ion or Li-Po cellphone battery violently venting as a result of charging past 4.1v. Generally with lithium-based cells, if they have been packaged into a battery then there is probably a basic protection circuit against overvolt, undervolt and shorts.
That said, I would still recommend charging through the mini-usb rather than trying to jury rig together some kind of interface to go between the battery and the contacts.
Click to expand...
Click to collapse
Yes, there's usually protection circuitry built-in, but i'm not going to tell someone i don't know, and therefore don't trust the persons knowledge, to put these circuits to the test...
I've been charging Lithium Ion (Both organic solvent and solid polymer) from my lab-supply several times, without blowing them up, but i have seen what happens when it goes wrong (And it's much scarier to see it in real life, than watch the videos...), and therefore i won't tell someone i don't fully trust to charge a cell without a charger.
Related
The Atrix's default adapter in an 5v = .85A, while the Ipad's is 5v = 2.1A. Is it safe for the battery to use this charger? I also have been using the ipod charger on my atrix too, should i countinue to use the ipod charger or does that have negitive effects too, ipod charger is 5v = 1A
Atrix: 5v = .85A
Ipod/Iphone: 5v = 1A
Ipad: 5v = 2.1A
Typically, a device will only pull what it needs, amperage-wise. The ratings on power supplies are, to my knowledge, always indications of maximum amperage, not any form of 'forced' current. Thus, the only time you need to be worried is if it is lower than your device's required input. You should be fine with either.
+1
That's correct. I actually spent a lot time researching that kind of stuff because I use electronic cigarettes and finding chargers for them was difficult. Anyways, as long as it's 5V it should be fine. They actually make AC adapters that are iPad "compatible", meaning that they are just rated at 2.1A but it still works with the iPhone which the OP has stated uses a lower Amperage.
ian426 said:
Typically, a device will only pull what it needs, amperage-wise. The ratings on power supplies are, to my knowledge, always indications of maximum amperage, not any form of 'forced' current. Thus, the only time you need to be worried is if it is lower than your device's required input. You should be fine with either.
Click to expand...
Click to collapse
Thank you, both of you.
Would it charge the same rate?
the fact that a device will pull as much as it needs is true, but that is true only to the devices, appliances, and anything that is using the electricity, not storing it - which is the case with the battery. any electrical device uses only as much power as it needs. for example: a 55watt house light bulb will only use .5 amps, (110 volts AC) even though the circuit is wired for 15 amps max.
When it comes to cellphones, the cellphone is the device that uses the power and the battery stores the power. during charging, battery will try to pull as much in as you will give it, unless there is a limiting factor involved. a limiting factor can be a charger it self, which will supply 1.0 amps, .85 amp max, or what ever the case may be. also there may be a limiting factor built in to the phones circuitry it self that would allow only so much to go through ( i seriously doubt though)
By plugging in to 2.1A charger, the battery will try to intake all 2.1 amps,
Pro: you are charging the battery in half the time.
Con: if it doesn't destroy the battery right away, the lifespan of it and usefulness decreases dramatically.
This is called overcharging the battery, do some research on that and you will find out that overcharging the battery is never a good thing.
2.1A is not enough to destroy the battery right away, but if you would have plugged in 5 or 10 amp charger, it probably would, i'm just saying this to explain the concept.
I personally do use a 1.0A charger that i have left over from previous cellphone (touch pro 2) and your ipod charger should be ok too, but I wouldn't use anything bigger then that.
a small experiment that you can conduct which may or may not work. compare the temperatures of the battery/cellphone while it is charging on .85amp charger and 2.1amp, when it is on a bigger charger, it should get a lot hotter, and that is what destroys the battery.
As far as my knowledge goes, i have taken enough classes about electricity and electronics, and have been working in the field for several years, so i hope i was helpful enough and explained it in simple enough terms for everyone.
hlywine said:
the fact that a device will pull as much as it needs is true, but that is true only to the devices, appliances, and anything that is using the electricity, not storing it - which is the case with the battery. any electrical device uses only as much power as it needs. for example: a 55watt house light bulb will only use .5 amps, (110 volts AC) even though the circuit is wired for 15 amps max.
When it comes to cellphones, the cellphone is the device that uses the power and the battery stores the power. during charging, battery will try to pull as much in as you will give it, unless there is a limiting factor involved. a limiting factor can be a charger it self, which will supply 1.0 amps, .85 amp max, or what ever the case may be. also there may be a limiting factor built in to the phones circuitry it self that would allow only so much to go through ( i seriously doubt though)
By plugging in to 2.1A charger, the battery will try to intake all 2.1 amps,
Pro: you are charging the battery in half the time.
Con: if it doesn't destroy the battery right away, the lifespan of it and usefulness decreases dramatically.
This is called overcharging the battery, do some research on that and you will find out that overcharging the battery is never a good thing.
2.1A is not enough to destroy the battery right away, but if you would have plugged in 5 or 10 amp charger, it probably would, i'm just saying this to explain the concept.
I personally do use a 1.0A charger that i have left over from previous cellphone (touch pro 2) and your ipod charger should be ok too, but I wouldn't use anything bigger then that.
a small experiment that you can conduct which may or may not work. compare the temperatures of the battery/cellphone while it is charging on .85amp charger and 2.1amp, when it is on a bigger charger, it should get a lot hotter, and that is what destroys the battery.
As far as my knowledge goes, i have taken enough classes about electricity and electronics, and have been working in the field for several years, so i hope i was helpful enough and explained it in simple enough terms for everyone.
Click to expand...
Click to collapse
I might have to double check that. There is a chance that there is some sort of limiting circuit between the wall and the charger for the Atrix... I am fairly certain at least laptops do so. I will see if I have a stronger charger and I will check the voltage across the leads in the atrix... if I can.
Its not voltage that you should be checking, voltage should be same in all usb chargers, about 5 volts, you should be checking amps
hlywine said:
Its not voltage that you should be checking, voltage should be same in all usb chargers, about 5 volts, you should be checking amps
Click to expand...
Click to collapse
My mistake... realized that after I posted it.
Also -- I do not have any USB charger that is over one amp, so I cannot check this. If anyone has a mutineer and a more powerful charger, they could do so.
The important factor is the Voltage which is at 5V for both the iPad and Atrix chargers. Whether it is rated at 10W or 5W does not matter because that just reflects the capacity for the current. And the charger is "rated" at 2.1 meaning it can handle that current rather than meaning it will force it. The "draw" of current is decided by the phone itself, as long as the Voltage is identical, the other factors should not matter.
If you read the "Summary" here it will say that, with the iPad charger, you can charge an iPhone which is similar to the Atrix in charging specs:
http://support.apple.com/kb/HT4327
And here are a couple more links:
http://www.youtube.com/watch?v=-ZjRm8nkv9Q
http://munnecke.com/blog/?p=836
hlywine said:
the fact that a device will pull as much as it needs is true, but that is true only to the devices, appliances, and anything that is using the electricity, not storing it - which is the case with the battery. any electrical device uses only as much power as it needs. for example: a 55watt house light bulb will only use .5 amps, (110 volts AC) even though the circuit is wired for 15 amps max.
When it comes to cellphones, the cellphone is the device that uses the power and the battery stores the power. during charging, battery will try to pull as much in as you will give it, unless there is a limiting factor involved. a limiting factor can be a charger it self, which will supply 1.0 amps, .85 amp max, or what ever the case may be. also there may be a limiting factor built in to the phones circuitry it self that would allow only so much to go through ( i seriously doubt though)
By plugging in to 2.1A charger, the battery will try to intake all 2.1 amps,
Pro: you are charging the battery in half the time.
Con: if it doesn't destroy the battery right away, the lifespan of it and usefulness decreases dramatically.
This is called overcharging the battery, do some research on that and you will find out that overcharging the battery is never a good thing.
2.1A is not enough to destroy the battery right away, but if you would have plugged in 5 or 10 amp charger, it probably would, i'm just saying this to explain the concept.
I personally do use a 1.0A charger that i have left over from previous cellphone (touch pro 2) and your ipod charger should be ok too, but I wouldn't use anything bigger then that.
a small experiment that you can conduct which may or may not work. compare the temperatures of the battery/cellphone while it is charging on .85amp charger and 2.1amp, when it is on a bigger charger, it should get a lot hotter, and that is what destroys the battery.
As far as my knowledge goes, i have taken enough classes about electricity and electronics, and have been working in the field for several years, so i hope i was helpful enough and explained it in simple enough terms for everyone.
Click to expand...
Click to collapse
thanks live4nyy, i never saw those before. with all the stuff described there, the only conclusion possible is that each device has its built in limiter on how much it will pull while charging, or apple figures that with a bigger charger your battery on ipod/iphone will still last you past the 1 year manufacturers warranty expiration date, but barely past that date, instead of lasting 3-5 years like its suppose to. what ever the case is with apple, i just hope we have a safety built in into our atrix phones. I guess the only way to find out is to actually check the amperage while its charging.
I'm almost positive that the lithium batteries in phones these days are "rated" for specific current and have built in circuits that dictates the "flow", which is also the same thing that causes the battery to go into a "trickle" charge when near capacity. Just for that there has to be some sort of "regulation" happening. See also here:
http://science.howstuffworks.com/environmental/energy/question501.htm
But I agree, better safe than sorry. If you happen to have an iPad charger that you plan on using let me know how it goes. I'm curious as well.
hlywine said:
thanks live4nyy, i never saw those before. with all the stuff described there, the only conclusion possible is that each device has its built in limiter on how much it will pull while charging, or apple figures that with a bigger charger your battery on ipod/iphone will still last you past the 1 year manufacturers warranty expiration date, but barely past that date, instead of lasting 3-5 years like its suppose to. what ever the case is with apple, i just hope we have a safety built in into our atrix phones. I guess the only way to find out is to actually check the amperage while its charging.
Click to expand...
Click to collapse
********
UPDATE 1/10/2012
This below charger and USB adapter WORKS LIKE A CHARM!!!
Charged fast... from 20percent to 100 percent in 2 hours!!!!!
I can now STOP using the OEM charger which is crap!
Admin: Please add this to the list of working prime accessoriesMy first transformer Prime had charging issues, ( would not charge intermittently) and I found the OEM charger that ships with the prime to be sub-par.. So:
After checking out NUMEROUS threads, I just purchased the following charger and USB adapter from Radio Shack to Use with my Prime:
This particular model has been confirmed to work on the original Transformer-
Enercell AC to DC power adapter 12vdc 1.5A
Radio Shack Model # 273-358
http://www.radioshack.com/product/index.jsp?productId=3807944
used together with this USB adapter:
Model #273-227
http://www.radioshack.com/product/index.jsp?productId=3643549
Does anyone know if the above Enercell 12V 1.5A charger should work on the Prime?
see post #104 here in this thread:
http://forum.xda-developers.com/showthread.php?t=1087321&page=11
Also, can someone confirm the Tip polarity I should use? (I believe the prime uses Positive tip polarity just like the original transformer did?)
http://www.12volt-travel.com/knowledgebase/universal-adapter-tip-polarity/
Thanks for any feedback!
********
UPDATE 1/10/2012
This above charger and USB adapter WORKS LIKE A CHARM!!!
Charged fast... from 20percent to 100 percent in 2 hours!!!!!
I can now STOP using the OEM charger which is crap!
Admin: Please add this to the list of working prime accessories
********
UPDATE 1/10/2012
This above charger and USB adapter WORKS LIKE A CHARM!!!
Charged fast... from 20percent to 100 percent in 2 hours!!!!!
I can now STOP using the OEM charger which is crap!
The charger doesn't even get barely warm while it charges... much better than OEM for me!
Admin: Please add this to the list of working prime accessories
I thought I read somewhere that fast charges aren't good for the long term viability of lithium-based batteries.
---------- Post added at 07:27 PM ---------- Previous post was at 07:25 PM ----------
http://batteryuniversity.com/learn/article/how_to_increase_the_runtime_of_your_wireless_device
Simple Guidelines to Prolong Lithium-ion Batteries
Do not discharge Li-ion too low; charge more often.
A random or partial charge is fine. Li-ion does not need a full charge.
Limit the time the battery resides at 4.20/cell (full charge), especially if warm.
Moderate the charge current to between 0.5C and 0.8C for cobalt-based lithium-ion. Avoid ultra-fast charging and discharging.
If the charger allows, lower the charge voltage limit to prolong battery life.
Keep the battery cool. Move it away from heat-generating environments. Avoid hot cars and windowsills.
High heat and full state-of-charge, not cycling, cause short battery life in laptops.
Remove battery from laptop when used on the power grid.
Click to expand...
Click to collapse
Yeah, I would avoid third-party chargers. Have had a lot of problems with them for laptops.
clankfu said:
Moderate the charge current to between 0.5C and 0.8C for cobalt-based lithium-ion. Avoid ultra-fast charging and discharging.
Click to expand...
Click to collapse
Taking 2 hours to charge implies a 0.5C charge rate.
What's the rated voltage, current and wattage of the stock charger anyway?
Please note that the above charger won't work overseas. It's only got 110V.
webbrowser said:
Taking 2 hours to charge implies a 0.5C charge rate.
What's the rated voltage, current and wattage of the stock charger anyway?
Click to expand...
Click to collapse
Stock charger is rated 15 volts DC @ 1.2 Amps
This radio Shack charger That is working for me is rated 12volts DC @ 1.5Amps.
I read the Transformer specs required to chagre are 11V to 15V DC @ 1A to 2A max
This charger fits within these specs, so that is why it works pretty well. The TP and the charger itself do not get hot at all, so I don't think this is causing any issues with the battery. Does anyone think a slightly quicker charge time will harm the battery long term?
Li-Ion Batteries are sensitive to fast charging. While it is within specs, your long term battery life could be affected. There is probably a reason that Asus decided to stay at the very bottom end of the spec.
nslayden said:
Li-Ion Batteries are sensitive to fast charging. While it is within specs, your long term battery life could be affected. There is probably a reason that Asus decided to stay at the very bottom end of the spec.
Click to expand...
Click to collapse
I have done additional research due to above feed back in regard to Li-Ion's sensitivity with faster chargers.
Apparently, you are correct in regard to long term battery life concerns. I have only done 3 charges so far with the Radio Shack charger. I will let it drain down and switch over to the stock for now and just keep this other one as a backup. Is charging at 300MA more than OEM that much more of significant concern?
Better safe than sorry. Hopefully the few charges I have done did not cause any harm.... If the stock charger goes bad again though, I don't know if I would buy another one....
What was interesting is how hot the stock charger becomes in comparison to the radio shack model, which barely gets even warm. I always was a believer that more heat means less efficiency, so I'm somewhat confused, but I don't want to risk shortening the battery life, so I will go back to OEM stock charger for now, but reluctantly.
I wonder How these "alternative" chargers have effected the batteries for others with the original transformer?
That's an expensive charging setup... nearly $40 eek
mazjohn said:
I have done additional research due to above feed back in regard to Li-Ion's sensitivity with faster chargers.
Apparently, you are correct in regard to long term battery life concerns. I have only done 3 charges so far with the Radio Shack charger. I will let it drain down and switch over to the stock for now and just keep this other one as a backup. Is charging at 300MA more than OEM that much more of significant concern?
Better safe than sorry. Hopefully the few charges I have done did not cause any harm.... If the stock charger goes bad again though, I don't know if I would buy another one....
What was interesting is how hot the stock charger becomes in comparison to the radio shack model, which barely gets even warm. I always was a believer that more heat means less efficiency, so I'm somewhat confused, but I don't want to risk shortening the battery life, so I will go back to OEM stock charger for now, but reluctantly.
I wonder How these "alternative" chargers have effected the batteries for others with the original transformer?
Click to expand...
Click to collapse
I wouldn't worry if I were you. What you bought is just an adapter with a USB socket. The part which decides how to charge the battery is inside the tablet. The requirement for the adapter is to have the same voltage as the original one and at least as much current ( meaning 1.2A or more). The tablet will only take what it needs.
Be careful http://m.youtube.com/#/watch?desktop_uri=/watch?v=SMy2_qNO2Y0&v=SMy2_qNO2Y0&gl=US
susko said:
Be careful http://m.youtube.com/#/watch?desktop_uri=/watch?v=SMy2_qNO2Y0&v=SMy2_qNO2Y0&gl=US
Click to expand...
Click to collapse
It's always easy to scare people. It does say in the description of the movie that he did it by removing the protection circuit. They are designed with protection, so of course they will blow up without one.
Dude why so serious?
It was a joke thus a smiley was implemented. It is quite difficult to do that to a battery. Although I have seen some insane people in the RC hobby community destroy expensive cars and helicopter this way.
Lipo+ignorance=Hollywood style explosions
I saw the smile, don't worry. It is just that most of people, especially when they do not have the knowledge about something, tend to see the bad part (I'm also guilty of this, not in this domain though ).
So, it was not anything against you, the video is entertaining. I just wanted to put people at ease.
Charging Issues
It does not matter the type of rechargeable battery, any "quick charge" will reduce the battery life. I personally don't think 300mA is that much of a difference, but am sure the battery life would be reduced somewhat over time. Nor would I worry much from just 3 charges.
However I don't think we should have to shell out an additional $40 just because Asus can't build quality components. Mine quit charging consistently yesterday (week and a half). I guess we can put it in the same category as GPS...non professional and spotty at best.
EatMy45 said:
However I don't think we should have to shell out an additional $40 just because Asus can't build quality components. Mine quit charging consistently yesterday (week and a half). I guess we can put it in the same category as GPS...non professional and spotty at best.
Click to expand...
Click to collapse
Don't worry, ASUS will remove the charger from the SPECs and say it is no longer supported, problem solved...
Is there any charging mats out there that will be compatible with TF101?
thanks. sean...
nope unless there is one that charges unmodified lithium ion batteries by induction
also transformer (i think) requires ~12 volts to charge and i don't think power mats can put out that much
it would be so practical it was built in. Imagine charging your phone on your inducted table, no more charging problem again!
sadly to answer the question, i dont think one will exist as the battery is non removeable.
My TouchPads do that elegantly.
I am afraid the TFormer does not have pickup on battery-
So they have projects everywhere that install them. Just need a Palm kit and a induction back plate. It'd thin and you solder it to the battery contacts.
Problem, like said, it only gives 5v USB power which the transformer probably wouldn't use... or so they say.
EXT LTE Galaxy Nexus - 4.0.4
Asus Transformer - ICS
player911 said:
So they have projects everywhere that install them. Just need a Palm kit and a induction back plate. It'd thin and you solder it to the battery contacts.
Problem, like said, it only gives 5v USB power which the transformer probably wouldn't use... or so they say.
EXT LTE Galaxy Nexus - 4.0.4
Asus Transformer - ICS
Click to expand...
Click to collapse
Considering that Lipo cells are 4.2v max, and the 7.4v Lipo actually contains 2 3.7v Lipos (4.2v at max charge) if you could solder the chargers to each cell (not entirely impossible, if you know your way around a Lipo battery) you could probably get the cells to charge independent of one another, but the other problem would be balancing the cells, you may need another circuit added between the two Lipo cells to achieve this (I am not familiar with the wiring on the TF Lipo). I know that the charger is 15v+ simply because the dock also has a 7.4v lipo and the two must both charge from one charger, but as long as you have 8+ volts to the TF itslef it should charge the lipo, or 5v*2 induction chargers?
Someone willing to sacrifice their TF (potentially) would be required to test this though.
Thanks for the input. Basically your saying it is out of my league without a walkthrough holding my hand lol.
Me and electricity don't get along. I have no fear of solder but I'd probably do put the poles on backwards...
I want to make a bike charger for my S3. I made sure the converter is working and can deliver more than 2A of constant current at 5V.
As long as the phone does not detect the converter as a proper charger, it won't draw more than 500mA which is not enough to maintain charge while navigating or using apps. I have tried to measure out the charger that came with the phone and found out that the data lines are shorted. Apart from this, there seems to be no connection from the data lines to the supply voltage. I tried to replicate this on my selfmade charger but still the phone won't draw more than 500mA. I tried searching the net for info on the charging circuit but can't seem to get anywhere. I would like avoid cracking open the original charger.
Does anyone here have an idea what has to be done so the phone will draw more current from a homemade charging device?
you can always get a Kernel with charging control and up the amperage, but that's more of a workaround
There's a reason why i don't like workarounds like this. It violates usb specifications and may lead to damage to a regular usb port if handled improperly. It may be possible that i am missing something. Maybe i'll get another original charger and dig deeper into this matter. I'll post results as soon as available
Noume said:
I want to make a bike charger for my S3. I made sure the converter is working and can deliver more than 2A of constant current at 5V.
As long as the phone does not detect the converter as a proper charger, it won't draw more than 500mA which is not enough to maintain charge while navigating or using apps. I have tried to measure out the charger that came with the phone and found out that the data lines are shorted. Apart from this, there seems to be no connection from the data lines to the supply voltage. I tried to replicate this on my selfmade charger but still the phone won't draw more than 500mA. I tried searching the net for info on the charging circuit but can't seem to get anywhere. I would like avoid cracking open the original charger.
Does anyone here have an idea what has to be done so the phone will draw more current from a homemade charging device?
Click to expand...
Click to collapse
The key in shorting out the data lines to achieve FAST charge rate is that the Phone sees it as shorted at the Micro Usb connection point of the phone. Anywhere else down the line is irrelevant. Depending on the Kernel, most phones slow down the charging rate after...hmmm...anywhere between 70-100%. The closer to full charge...the slower the charge rate gets...until it becomes a trickle charge...just in case you don't know.
If your still having issues, please post back with a more detailed explanation of your wiring and parts as best as you can and I will help you with it.:good:
[Solved] Charger for S3
Considering your suggestions i was asking myself if i've done everything right and as it turned out, i hadn't.
I do know that chargers current depends largely on the charging state of the battery. Good chargers start initiate completely drained batteries with a low current, which is ramped up to the max at around 5-10%. After reaching 85-90% the current drops down to small trickle pulses as the charging finishes. These values can be adjusted within the firmware/kernel to get a longer battery life/more power. That's why i always do charging tests with a battery that is at least down to 33%.
But back to topic now
Using an oscilloscope i found my switching regulator to have about 150mV ripple voltage which apparently is a bit more than the S3 is willing to take. After sorting it out, ie. resoldering a cold joint, it finally works as expected, the ripple voltage is now around 32mV. The regulator could deliver more than 2A before, but only with about 600mV ripple, which i unfortunately overlooked
Charging the phone's completely drained battery, i get around 320-340mA current draw from the battery(12Vnom LiFePO4) .
The phone takes around 950mA at 5.1V. I wonder why earlier charging circuits had to be so "complicated" like with Apple phones or Galaxy Tab, while most newer phones are happy with just shorted data lines.
The circuit i use is composed of a three-phase voltage doubling rectifier, that takes bike from a generator hub in the front wheel. This one is connected to a battery for storage and buffering. A small switching regulator provides 6V 600mA for the lighting system. A larger LM2596-based regulator (you can get those modules around $1.50) provides power for my S3 and a microcontroller that will later be used for monitoring the systems voltages and rotational speed of the front wheel. EAGLE layout files for circuit and PCB will be finished soon.
Heyyyy guys, it's been a while now since my one x+ died on me...
Some part on the motherboard probably got fried as it won't charge.
Can anyone tell me what the pins of the battery are, like what's the positive and negative pole?
There are 6 pins, 2 red, 1 white, 1 green and 2 black.
Which one can I use to charge the battery and on the phone, what pins should I use to get the current flowing through the phone?
I know it's just the charging circuit as it powers up when the battery is charged, and no it doesn't smoke or get any warm at all when I plug it in, thus, there definitely is a defect.
I just want to use this phone like on my desk or something because I can't sell it at this state anyway and the phone I use atm is an s3 mini
Hi
Unfortunately I haven't the answer to your question, but tomorrow or friday i'll give my HOX battery to a my colleague that is an electrical engeneer to check the real capacity of battery...and i'll try to give you an answer.
I think that the general rules "RED is POSITIVE" and "BLACK is NEGATIVE" is always valid, but maybe the two red wires have a different voltage....
However i'll let you know soon.
Could you do me a favor? I need a photo of HOX+ battery! Could you take a photo of your and reply to my post here?? http://forum.xda-developers.com/htc-one-x2/help/hox-battery-replacement-photo-t3026505
Thanks!
K-Skulz said:
Hi
Unfortunately I haven't the answer to your question, but tomorrow or friday i'll give my HOX battery to a my colleague that is an electrical engeneer to check the real capacity of battery...and i'll try to give you an answer.
I think that the general rules "RED is POSITIVE" and "BLACK is NEGATIVE" is always valid, but maybe the two red wires have a different voltage....
However i'll let you know soon.
Could you do me a favor? I need a photo of HOX+ battery! Could you take a photo of your and reply to my post here?? http://forum.xda-developers.com/htc-one-x2/help/hox-battery-replacement-photo-t3026505
Thanks!
Click to expand...
Click to collapse
Sure! I'll upload it once I'm home.
And I don't seem to be able to hook up my voltmeter to measure the voltage of the battery since the pins are a little... Well... Too small, obviously
And I found out one of the red pins on the phone side don't make the 'beep' sound when hooked up to my multimeter, when touching the GND...
I confirm that you can charge the battery using the either of two red wires (that are POSITIVE pole) and either of two black wires (that are NEGATIVE pole)...They have the same voltage (3.8v but it depends by the charge of battery...it can vary from about 2.75v at 0% and about 4.1v at 100%)
The other two wires (green and white) are probably the internal temperature sensor.
The problem is that if you want to manually charge the battery with a "standard" phone charger you have to calculate the charging time!!!
Because without the charging circuit board integrated in the phone there aren't any overvoltage and overcharge controls on the battery and it will be damaged if you charge it too much!!! (With risk of FIRE and EXPLOSION of the battery!!!)
I suggest you to buy a "smart" 3.7v Li-ion battery charger to manually charge your battery...it's a really cheap accessories and it's the safety and easy way to charge li-ion batteries.
K-Skulz said:
I confirm that you can charge the battery using the either of two red wires (that are POSITIVE pole) and either of two black wires (that are NEGATIVE pole)...They have the same voltage (3.8v but it depends by the charge of battery...it can vary from about 2.75v at 0% and about 4.1v at 100%)
The other two wires (green and white) are probably the internal temperature sensor.
The problem is that if you want to manually charge the battery with a "standard" phone charger you have to calculate the charging time!!!
Because without the charging circuit board integrated in the phone there aren't any overvoltage and overcharge controls on the battery and it will be damaged if you charge it too much!!! (With risk of FIRE and EXPLOSION of the battery!!!)
I suggest you to buy a "smart" 3.7v Li-ion battery charger to manually charge your battery...it's a really cheap accessories and it's the safety and easy way to charge li-ion batteries.
Click to expand...
Click to collapse
Thanks, and yeah, I aknowledge the consequences when it's done wrong.
That's why I asked, and I do have a "smart" charger, you let the pins of it touch the battery's charging pins and it stops charging when full. It should be around 3.7V, gotta check that later.