Build a new battery - Hardware Hacking General

Hello,
i have an idea because the battery of my DELL Streak 7 is quite bad. So i thought, if i get another li-ion battery from a notebook for example, i could build it into the device. Would it be detected?
greetz.

I think it should, I mean why not, provided you do the connections properly. 1 thing, the battery specs perhaps must be same or nearly same as the original battery.

What do you mean with specs? I need a more powerful battery so the mAh should be different.

Main problem is:
1) If the Streak uses an in-pack fuel gauge it could be difficult.
2) Getting a battery of the correct dimensions to fit is going to be extremely difficult
However, if you don't mind issues with form factor, you could:
Make a dummy battery from plastic or wood
Run wires out from this dummy battery to an 18650 holder
Put in a protected 18650 - easy, 2-3 AH battery.
Form factor will suck though
Which reminds me, I need to make a dummy battery for my GS2 to measure power consumption.

I solved it with a external battery. But i will think about it in future.
Thanks for the answers

No wonder the Samsung Galaxy battery has such a short duration of power...If you think about it, Duo core 1.2Ghz is even STRONGER than most laptops...and their battery range ( for Laptops ) even EXEEDS 4200 mAh...and here we have a Smartphone with only 1650 mAh...Maybe its because of the bigger 15.6" screen's wattage that it has to pull...

RobinHoodSnr said:
No wonder the Samsung Galaxy battery has such a short duration of power...If you think about it, Duo core 1.2Ghz is even STRONGER than most laptops...and their battery range ( for Laptops ) even EXEEDS 4200 mAh...and here we have a Smartphone with only 1650 mAh...Maybe its because of the bigger 15.6" screen's wattage that it has to pull...
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Click to collapse
Biggest draw in any system in the backlight for the display, phones or laptops. Secong in laptops is non-SSD hard drives while second in phones is wireless transmission (network mostly but bluetooth and wireless as well).
In terms of the battery the biggest spec you have to worry about is Voltage. most devices regulate what comes off the battery to an extent but still requires it to be within a certain range. Basically, matching is the best and definitely don't try to put a 12V battery in a spot which previously had a 3.7V battery! Unless of course you want to see some fireworks (well, atleast some smoke)! :Þ

Wow, i didnt think that anybody will look at this thread
If anybody plans to build a new battery, post it here

onlymojo said:
Biggest draw in any system in the backlight for the display, phones or laptops. Secong in laptops is non-SSD hard drives while second in phones is wireless transmission (network mostly but bluetooth and wireless as well).
In terms of the battery the biggest spec you have to worry about is Voltage. most devices regulate what comes off the battery to an extent but still requires it to be within a certain range. Basically, matching is the best and definitely don't try to put a 12V battery in a spot which previously had a 3.7V battery! Unless of course you want to see some fireworks (well, atleast some smoke)! :Þ
Click to expand...
Click to collapse
Also, only the lowest-power laptops are clocked at 1.2 GHz - and there's MASSIVE differences between old 1.2 GHz laptop CPUs and dual-core Cortex-A9.
TDP of an Intel SU3500 ULV is 5.5 watts - that's in addition to the motherboard chipset and GPU.
TDP of the lowest-power Core i3 is 17 watts
Atoms start at 1.2 watts for the 1.2 GHz single-core Z600 and go upwards from there. Again - add chipset and graphics to that.
Compare to, for example, OMAP4460 - the data I'm seeing indicates a max consumption of around 2.6W for the whole chip - CPU, GPU, and all onchip peripherals (typically found within the motherboard chipset on desktop systems.)

heat dissipation (phone case)
a big mistake people make a lot is charging their phones while their phone casing is on, or even using heavy apps with the phone casing on. Phone case covers the battery and increases heat dissipation thus reducing battery life quickly. take note peeps

exebreez said:
Hello,
i have an idea because the battery of my DELL Streak 7 is quite bad. So i thought, if i get another li-ion battery from a notebook for example, i could build it into the device. Would it be detected?
greetz.
Click to expand...
Click to collapse
No man you cant do it.

Very good tip on removing casing from battery to extend life! Mm battery life sucks as is.....I will be enjoying your tip ty
Sent by B rad on my 4G Revolution using XDA

thinking about doing something like this with my desire hd. I have 3 extended 1600mah batteries. I was thinking about modding a case and running wires to the other battery to increase the capacity. Just cutting a battery sized hole in my case would work. The only problem i see is that the if there is a chip on the battery that measures the level. Although i could just rip it out and see how that works. Itd be nice to have a 3200mah battery
Sent from my Desire HD using xda premium

I don't understand why everyone thinks about doing stuff like this. Building batteries is best left to the professionals. They put lots of thought into the design and construction. They include temperature sensors, voltage and current so you can't overcharge, over discharge, or anything in between.
http://www.ladyada.net/library/batteries.html
Why not buy just a large extended battery that is purpose built?

giritrobbins said:
I don't understand why everyone thinks about doing stuff like this. Building batteries is best left to the professionals. They put lots of thought into the design and construction. They include temperature sensors, voltage and current so you can't overcharge, over discharge, or anything in between.
http://www.ladyada.net/library/batteries.html
Why not buy just a large extended battery that is purpose built?
Click to expand...
Click to collapse
well for my desire hd you cant get more than a 1500mAh extended battery. 1500mAh being actual size from a trusted brand. So battery life sucks
Sent from my Desire HD using xda premium

stumpyz9 said:
thinking about doing something like this with my desire hd. I have 3 extended 1600mah batteries. I was thinking about modding a case and running wires to the other battery to increase the capacity. Just cutting a battery sized hole in my case would work. The only problem i see is that the if there is a chip on the battery that measures the level. Although i could just rip it out and see how that works. Itd be nice to have a 3200mah battery
Sent from my Desire HD using xda premium
Click to expand...
Click to collapse
If your phone uses an in-pack fuel gauge - not worth the hassle.
Some devices, like most Samsungs, use an in-system fuel gauge - the pack has nothing but the basic protection circuits (over/undervoltage lockout, overcurrent/short protection) and sometimes an ID resistor, so if you wire in a larger battery with the same protection circuits (and possibly an ID resistor to the correct pin) it'll work.
DO NOT mess with unprotected Lithium-Ion packs or cells! It's a great way to make them go boom!
The same place giritrobbins linked SELLS prebuilt packs with protection circuitry including purpose-built chargers - http://www.adafruit.com/category/44
Getting any of these to fit in the form factor of an existing device will be next to impossible, but you can use some of the products above to make an external pack for devices that don't put fuel gauge or management circuitry into the pack (such as, as I stated before, most Samsungs).
http://www.adafruit.com/products/353 - that's a pre-matched 3-cell 18650 pack that includes all required protection circuitry. It would be electrically compatible with, for example, the battery in my Galaxy S II (other than not having NFC like my battery does, and someone would have to wire a resistor between the ID contact and ground of a dummy battery to work with a GSII.)

Related

Has anyone seen this ...

Im looking for an X1 replacement batter with the charger. I have this same exact thing for my HTC Touch Cruise and believe me it is a godsend. Instead of sitting there for my phone to charge, I have one in the dock charging all the time. So when I run low to dead just swap and in seconds I have new juice.
Link to the htc touch cruise one that i have
http://cgi.ebay.com/1350mAh-Battery...14&_trkparms=72:1205|66:2|65:12|39:1|240:1318
unless your a really power user you probably won't need to charge the battery that often given hercules is powering the x1 i think with heavy use you'd be good charging it probably once every 10-12 hours
What about with WiFi use?
I know on my Wizard the battery goes in about 2 hours with WiFi active even if its just idling with Messenger. Have they actually improved that much over the years? I'm hopeful but also skeptical.
WMVWifiRouter will kill your battery in an hour and a half.
I'd be curious to know if there are any reliable aftermarket batteries. Buying any Sony OEM parts are always ridiculously expensive and many aftermarket batteries don't work well with Sony products.
well based on what i've been reading about the X1 it's supposed to have a nice increase in battery life compared to our current HTC phones. supposedly sony made a special project just for the phone codename Hercules it's supposed to be using a 1800 mah li poly in stead of what we use in our current phones which is li ion supposedly using the li poly is going to give the battery a much needed boost that all ppc's need to go all day or maybe a couple of days given the usage
Li-poly batteries is over 20% higher than that of a classical Li-ion battery and they store more energy than nickel-cadmium (NiCd) and nickel metal hydride (NiMH) batteries of the same volume.
When compared to the lithium-ion battery, Li-poly has a greater life cycle degradation rate. However, in recent years, manufacturers have been declaring upwards of 500 charge-discharge cycles before the capacity drops to 80% (see Sanyo). Another variant of Li-poly cells, the "thin film rechargeable lithium battery", has been shown to provide more than 10,000 cycles.
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Click to collapse
stole that from the wiki page

Any Same Shape Battary?

hi guys just wondering if anyone knows of a battery other than the original which is the same shape,
pretty sure there will be one
either samsung, nokia, lg ect
the original battery on this devices is rubbish
thanks
You do realise that it being the same shape doesn't mean it will work?
There's a few other things you would need to check otherwise you risk at worse killing the battery or the phone.. or starting a fire.
I don't find it any worse than any other smartphone (I have to charge all my phones daily).. JuiceDefender is your friend here for prolonging battery life.
Also most batteries for phones are the same shape.. its square.. most are.. you need one the same dimensions, voltage, polarity, and chemical type.. as well as one that charges at the same rate and indicates full charge safely to the charging circuit. (Basically dont do it is what I'm getting at)
sambartle said:
You do realise that it being the same shape doesn't mean it will work?
There's a few other things you would need to check otherwise you risk at worse killing the battery or the phone.. or starting a fire.
I don't find it any worse than any other smartphone (I have to charge all my phones daily).. JuiceDefender is your friend here for prolonging battery life.
Also most batteries for phones are the same shape.. its square.. most are.. you need one the same dimensions, voltage, polarity, and chemical type.. as well as one that charges at the same rate and indicates full charge safely to the charging circuit. (Basically dont do it is what I'm getting at)
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Click to collapse
I believe the opposite, as long as the battery fix, which won't fix until it's for your phone, you'll be fine...
The truth is, each phone has it's own size/shape from where the battery gets connected into sockets, not sure about zte blade but that is how it works for nokia, samsung, lg, motorola...
This is the battery of the Zte blade with 1300 mAh when the stock battery is 1250 mAh so this one's a better one so if you want to buy it, buy it

[Q] connectiong external battery directly to internal one.

Is it possible/safe to connect an external battery of same voltage but different mAh directly to the internal battery of a tablet to raise its mAh?
I am thinking about moding a tablet case to have a built in battery pack for my Iconia a500 tablet. I can easily squeeze 4 cell phone batteries in between the folds and make two 3.6v 3000mAh(or higher) battery pack with out adding much bulk or weight to it. can probably squeeze a usb hub in there too while i am at it.
I looked at the internal battery and it looks like i can splice its wires and add a connector to hook to the two 3.6v packs for easy connection.
I don't know much about electronics, but from my limited knowledge and layman point of view, as far as the tablet is concerns, it will just have a higher capacity battery, wont it?
can it be done safely without any other electronic components?
I'm not expert in that matter, but I think there's LiIon battery, and AFAIK it may make some confusement to your Fuel Gauge IC and Battery Charging IC, as these are probably calibrated to work with that certain battery type and capacitance. But I don't believe it may damage something if you connect it paralelly.
I would be careful with that if I were you. While it seems simple enough, batteries are much more complex than just voltage and capacity.
Most of the time, external batteries just go through the charging connection of the device so it can handle the power itself. If you connect it directly, you may bypass some part of the charging circuit (often times there's a circuit in the battery itself). Basically, I'm thinking the batteries may not fully charge or one will overcharge. It really depends on how it's set up. I'm not an expert with the design of rechargeable batteries though, so it may be safe.
In short, I would suggest connecting the batteries to the charger to extend your battery life. I'm sure others can offer additional insight.
A good read about batteries: http://batteryuniversity.com/learn/article/serial_and_parallel_battery_configurations
I can't comment on if it will work or if it is safe..
cellphone batteries have a built in protection to prevent them from overcharging or discharging, don't they?
The problem i have with connecting to the charging port is that it needs 12v. connecting 3 or 4 of battereis will give me either too little or too much volt. cant get 12v out of 3.7v batteries with out some kind of additional electronic parts to regulate the voltage. I don't have the sufficient knowledge to do that. this is why i figured ill do it directly. And charging would be simpler too if i can use the charger to charge both the internal and the external batteries at the same time.
Was hopping to hear from someone who did that already. I guess no one is brave/dumb enough to try it.
Sounds intresting looking forward for it
In a "perfect" environment this would be possible.
The inner resistance and voltage difference of the different batteries would even out the different capacity while charging.
You can avoid having these currents between the batteries by using diodes to separate the charging currents.
However my recommendations in terms of reliability, safety and efficiency is to use two or more batteries with the same capacity and dis-/charging curve.
is it the phone or the battery that cuts current when the battery is fully charged?
ridethisbike said:
is it the phone or the battery that cuts current when the battery is fully charged?
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Click to collapse
On most phones tablets etc. it's the device that cuts off the charging current when the battery is fully charged.
However nearly ever batteries has also a protection circuit that cuts off the battery in case of
under, over voltage and over current, sometimes even over temperature.
samotronta05 said:
On most phones tablets etc. it's the device that cuts off the charging current when the battery is fully charged.
However nearly ever batteries has also a protection circuit that cuts off the battery in case of
under, over voltage and over current, sometimes even over temperature.
Click to expand...
Click to collapse
ah, well it seems to me that if the battery has to take action, then you're doing it wrong.
I'm not sure exactly how diodes work so I can't comment on that, but definitely use like batteries (two 3000mAh batteries as opposed to one 3000mAh and one 3600mAh) as to not confuse the device about the charge, causing the 3600 to not get fully charged. just make sure they get connected properly (in parallel) and it should work just fine.
in reality its no different than someone using 4 car batteries to power their car audio system. as long as its done properly (in parallel), there is really no harm.
I wouldn't recommend it. While technically it is something that you can do like other posters have said the internal power system is configured in a particular matter. It is likely that the regulation and protection are minimal if they only expect the internal battery. There is also the issue of charging, if you did as you say, you would be discharging the batteries into each other if they weren't exactly at the same levels. So this isn't the recommend method.
What I would recommend you do is put them together so you get something over six volts (two 3.6V packs in series) and put a 5V regulator on it. Then connect it to a USB cable and charge through there. That way you utilize the systems built in protection, aren't messing with the battery connections and can swap it in much easier.
You can... as far as u meet these requirements.
1) notice ur original battery voltage..
2) buy some same kind of them, or u may use others, provided the voltage is same. If u can find higher watt-hour( current) battery of same voltage, go for it.
3) never mix up different amp/ voltage rated batteries together. Ie if u have 3.7v 3200ma batt, and planning to add one more batt in parallel to it go for another 3.7v 3200ma , and not 3.7v 1500ma or 3.5 v 3200ma batt.
4) if u cant find a higher capacity batt of same voltage, go for parallels. Ie join together the positives of two or more batt, and also join together their negatives too.. connect it to the batt terminals of tab,
5) no problems will be caused if u use high current batt, provided u have suited the correct voltage. In ur case u have to ensure proper voltage only. And current can increase to any value.. the system takes only what its needed.
6) the sad thing is it will take more time for charging. But never try to increase the charging current. It will damage the power section. But increase ur patients. Most of the tabs got 1-1.5 amp charger. Never increase the limits.
U may go for it. If u can manage these...
Sent from my HD2 using XDA App
giritrobbins said:
I would recommend it. While technically it is something that you can do like other posters have said the internal power system is configured in a particular matter.
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Yes, to charge with a constant current until a certain voltage is reached.
giritrobbins said:
There is also the issue of charging, if you did as you say, you would be discharging the batteries into each other if they weren't exactly at the same levels.
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Click to collapse
Yes, this is the main problem and it's also the reason i recommended using two batteries with the same capacity. Otherwise the constant charge and discharge depending on the size of the difference between the batteries makes the system very inefficient.
giritrobbins said:
What I would recommend you do is put them together so you get something over six volts (two 3.6V packs in series) and put a 5V regulator on it. Then connect it to a USB cable and charge through there. That way you utilize the systems built in protection, aren't messing with the battery connections and can swap it in much easier.
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Click to collapse
Which would make it even more inefficient.
showlyshah said:
3) never mix up different amp/ voltage rated batteries together. Ie if u have 3.7v 3200ma batt, and planning to add one more batt in parallel to it go for another 3.7v 3200ma , and not 3.7v 1500ma or 3.5 v 3200ma batt.
Click to expand...
Click to collapse
You can mix up different batteries when the voltage is the same, however this is not a the recommend way, since you will not encounter much gain in capacity.
The in terms of capacity smaller battery will be charged by the bigger one all the time.
However if you say i don't care about the efficiency then you can mix up for e.g. a 3.7v 3200mAh and a 3.7v 3000mAh battery.
samotronta05 said:
Yes, to charge with a constant current until a certain voltage is reached.
Yes, this is the main problem and it's also the reason i recommended using two batteries with the same capacity. Otherwise the constant charge and discharge depending on the size of the difference between the batteries makes the system very inefficient.
Which would make it even more inefficient.
You can mix up different batteries when the voltage is the same, however this is not a the recommend way, since you will not encounter much gain in capacity.
The in terms of capacity smaller battery will be charged by the bigger one all the time.
However if you say i don't care about the efficiency then you can mix up for e.g. a 3.7v 3200mAh and a 3.7v 3000mAh battery.
Click to expand...
Click to collapse
The issue when you connect them like that will always occur when they are in parallel (you need to add some logic or some diodes in there). Using the same ampacity battery will mitigate it to a point but the internal resistance of a battery will dictate how fast it drains down.
As for the charging, that isn't what i am saying. The internal circuitry that he cannot change is expecting a certain battery with certain characteristics. Putting a second battery in there in parallel will potentially mess with that stuff. If it doesn't realize the size of all the attached battery it will register a fault because it won't be charging correctly.
He isn't going for efficiency here. And a linear regulator is easy, if we want efficient we can do that too. I was just suggesting an alternative that could be easily done.
And the most important point is not about voltages but about chemistry. Different chemistry have different voltages and different knees where they drop suddenly.
The original battery is 7.4v 3350mah. and the charger is 12v 1.5a.
so matching or passing that with batteries I can fit in the space I want it to fit in is a problem.
I was going to use 4 i9000 1500mah batteries, which would fit perfectly, to make a 7.4v 3000mha. but that would be lower then the original. i guess i can try to find higher capacity batteries that i can fit in the case
But if i understand it correctly, the current will keep flowing from the larger capacity battery to the lower one, it will keep them at 100% until the original will drop to lets say 3000mah and then they will all drain at the same rate until they are all empty. and when i charge them, the charging circuitry will get its information only from the original battery, so it will keep charging until the original is full. it may not be as efficient, but it should still get me a significant boost, wouldn't it.
I suppose I could connect them all to make a 14.8v 1500mha with a 12v regulator and use the charging port, but that will leave me with the problem of charging the external pack. no idea how to do that. how do i cheaply and safely charge a 14.8v battery pack?
ronkoni said:
The original battery is 7.4v 3350mah. and the charger is 12v 1.5a.
so matching or passing that with batteries I can fit in the space I want it to fit in is a problem.
I was going to use 4 i9000 1500mah batteries, which would fit perfectly, to make a 7.4v 3000mha. but that would be lower then the original. i guess i can try to find higher capacity batteries that i can fit in the case
But if i understand it correctly, the current will keep flowing from the larger capacity battery to the lower one, it will keep them at 100% until the original will drop to lets say 3000mah and then they will all drain at the same rate until they are all empty. and when i charge them, the charging circuitry will get its information only from the original battery, so it will keep charging until the original is full. it may not be as efficient, but it should still get me a significant boost, wouldn't it.
I suppose I could connect them all to make a 14.8v 1500mha with a 12v regulator and use the charging port, but that will leave me with the problem of charging the external pack. no idea how to do that. how do i cheaply and safely charge a 14.8v battery pack?
Click to expand...
Click to collapse
Hey why are u going to make a 14.8v batt pack when urz original ones are 7.4??? I dont realy understand the logic. If u have extra batt, then make the pack like this
Batt pack of 7.4v × 2 and connect them in parallel, thatz all, no need to modify charging circuits, no need to regulate the voltage, and no loss in voltage/ current,
But if u make a high voltage pack, u have to regulate the o/p with some ic, and in turn u will suffer some v/c drop.
Sent from my HD2 using XDA App
i like to connect directly to the battery, but some seem to believe it is not wise if the mAh of the original is higher then the external pack.
The 14.8v pack with a 12v regulator option is for use with the tablet's charging connector which require 12v . A safer option, but leaves me with the charging problem.
ronkoni said:
i like to connect directly to the battery, but some seem to believe it is not wise if the mAh of the original is higher then the external pack.
The 14.8v pack with a 12v regulator option is for use with the tablet's charging connector which require 12v . A safer option, but leaves me with the charging problem.
Click to expand...
Click to collapse
http://www.ebay.com/itm/USB-2-0-fem...ultDomain_0&hash=item3f0cd836f3#ht_2792wt_902
that actually took me a lot longer to find than I had originally planned... lol. of course.... you're going to have to find the rest of your charger. but that'll be easy with that adapter
So its a about making a batt pack which u can connect to the tab via charging port? And use it like a backup when u r out of power?
If its ur idea, you may tell about the size of the pack, and how long u need to use it( ie backup time), if u do, i will find out the solution, also post ur current batt and charger spec.
And hope i can help with some circuits too..
Sent from my HD2 using XDA App
the idea is to have a battery pack that can fit in between the layers of the stand part of this tablet's case. the available space I want to use is about 2"x9" so since the space is limited, the batteries must be the flat type and be able to get 12v out of them and be able to charge them externally.
this is the original tablet battery and the charger is 12v 1.5a.
4x Samsung i9000 1500mAh batteries fits perfectly. and since i already got 2 extra ones laying around, might as well go with these batteries. unless it is possible to get 12v out of 3 batteries. then i can probably use 3 Samsung note 2500mAh batteries instead.
so, what circuitry do i need to make this thing power the tablet and get charged?
thought about getting one of these battery packs, take it apart and replace its batteries with mine. since it already got the necessary circuitry for regulating the voltage and for charging, it would cut down on the guess work and probably be cheaper to build. i think they use 3 batteries in there which would be better.

Chinese clone tablet M005 dual SIM battery improvement

I think I found the way of improving the battery of tablet as in the title. The battery compartment has dimentions 126.5x67.5x5 mm.
The original battery pack is wired and of capacity ca 1800 mAh so it does not last long.
I found on eBay batteries that will fit in the battery compartment, 3 of them, and they need to be connected in parallel. That will give 5400 mAh capacity at 3.7 V. Each battery has wires and has the size of 56x36x5 mm.
Here is the link:
http://www.ebay.com.au/itm/180850958176?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
I ordered the batteries and will post further when i install and test this solution. My only concern is that the batteries connected in parallel need to have identical voltages at the moment of soldering them together (to avoid high currents between them due to different voltages which would generate heat and even could destroy them) so probably they need to be first time connected while fully discharged.
mengagumkan said:
I think I found the way of improving the battery of tablet as in the title. The battery compartment has dimentions 126.5x67.5x5 mm.
The original battery pack is wired and of capacity ca 1800 mAh so it does not last long.
I found on eBay batteries that will fit in the battery compartment, 3 of them, and they need to be connected in parallel. That will give 5400 mAh capacity at 3.7 V. Each battery has wires and has the size of 56x36x5 mm.
Here is the link:
http://www.ebay.com.au/itm/180850958176?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
I ordered the batteries and will post further when i install and test this solution. My only concern is that the batteries connected in parallel need to have identical voltages at the moment of soldering them together (to avoid high currents between them due to different voltages which would generate heat and even could destroy them) so probably they need to be first time connected while fully discharged.
Click to expand...
Click to collapse
So the question is?
@UP:
It isn't forum for questions only.
@OP:
The second concern might be charging and fuel gauge, try to find out what are those ICs in your tablet, get datasheets and check if they need to have batt characteristics programmed by CPU, you might need to change parameters passed to them.
I would be very careful modifying the batteries. Li-ions have control circuitry inside of them that talk to the device and they have a very specific way they must be charge.
Even when they're used normally they have a bad habit of blowing up.
xHausx said:
Li-ions have control circuitry inside of them that talk to the device and they have a very specific way they must be charge.
Click to expand...
Click to collapse
Umm, if we're talking about cellphone's batteries. No they don't (at least not in phone models I've been studying). All I've seen in this class of batteries so far is +, - and thermistor pad (and sometimes NFC Antenna), everything else is calculated by fuel gauge and charging ICs, basing on the batt parameters they get from CPU and calibration data.
The thermistor should be monitored by the device, but afaik all li-ion batteries must have control circuitry to make sure they are charged correctly. Batteries with multiple cells also need it to balance usage and charging.
Of course there's always the exception, but li-ions are by their nature unstable, so caution is still advised when doing anything with them. A quick search of YouTube shows a lot about what they're capable of.
http://forum.xda-developers.com/showthread.php?t=906144
http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries/

Cell phone batteries

I have a lot of old cell phone batteries I had just purchased for my original Samsung galaxy just lying around would it be possible to maybe hook them all together somehow and make a large battery pack?
Sent from my SGH-T999 using Tapatalk 2
It would be possible. That's how those powerbanks works. But then it might be dangerous though
Sent from my GT-N7105 using xda app-developers app
Absolutely do not use unmatched batteries if constructing a battery pack, you are just asking for trouble - as in "fire" trouble.
They really need to all be at the same point in their life to work safely, which yours sound like they are not. Buy a battery pack, stay safe. (And yes, I build battery pack stuff, so I'm not against modding).
Cool thanks for the reply.
Sent from my SGH-T999 using Tapatalk 2
Imposible
mha93 said:
It would be possible. That's how those powerbanks works. But then it might be dangerous though
Sent from my GT-N7105 using xda app-developers app
Click to expand...
Click to collapse
No, it's crazy I believe what you're doing. The technology in the batteries of cell phones has changed little. Try looking for a larger storage battery that the manufacturer himself has designed. Greetings!
And please do not forget that the batteries must be disposed of in special places (organizations), for the sake of the environment. :angel:
sell/craigslist them and get a higher mAH battery.
Thank you guys. I think I will just look on Amazon instead lol I don't want to try anything dangerous
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The powerbank using multiple Li-ion is technically possible, but not-recommended.
The reasoning behind this, not all batteries are electrically the same. Unless you can confirm that the batteries all came from the same batch and where all subjected to the same amount of wear, the electrical properties of each Li-ion battery with be different.
Some simplified electrical theory explaining why it's not a good idea (slightly wordy and technical in nature but understandable) ,
Current itself is the flow of electrons, with each electron having some electrical energy. When these electrons flow thru a circuit, they end up colliding with the internal molecular structure of the path. Overtime the molecular structure of the Li-ion battery alters to a point where it no longer behaves as a practical battery (this is why they only last around two years or so).
when the electrons collide with the molecular structures some of the energy the electron carry is given off as heat. The rate of which this is produced is an exponential function of the current: (Heat in units of Wattage)=(current)^(2)*(Resistance), or as a function of the energy per electron (voltage) times the number of electrons (current).
some more important equations
Voltage=Resistance*current
in a series circuit, the voltage must all equal to zero with current being the same across all the components: (internal voltage drop of the battery)+(voltage drop of the load)=0 (This is known as Kirchhoff Voltage Law).
From this overtime more energy is lost within the battery due to its increasing resistance, so for a device needing a minimum voltage, more current is needed to supply the same amount of energy at one point in time
Unless the current is regulated, the battery could be subjected to more heat causing a combustion hazard.
This is why batteries need current regulation (flow of electrons).
Hope this gives a rough idea why its best to consider consumer/professional UL listed products.
Joe (Electrical Engineering Student)
any new tech other than Li-Poly
Maybe rather....
Third party batteries (good ones) and power-batteries are nowadays good solution for longer battery life. Some batteries are slightly bigger to "pack" more mAh and get delivered with the covers which fit the bigger battery size.
Possible but better don't do it
I think it's possible but all of them should have the same voltage and capacity...
Then other technical problems might occur.

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