Database Develop

Building a Nook Color extended battery

So after looking at the teardown and assembly info online, I've started to percolate a notion in my head to double the battery capacity of the NC.
My thinking is that if you sacrifice a bit of structural reliability by cutting out the portion of the plate the battery is on, you could cram another NC battery, scavenged from the ruins of a dead one, into there and wire it in parallel. The end result would be a heavier, probably slightly girthier, NC, with 8000mAh of life. I don't care how bright your screen is or how many rooted roms you're using, that fool will last a looooooong time.
My question is primarily for electrical folks here: any pitfalls to watch out for? Do we know if there's any circuits in the battery itself that might interfere or is the battery unit just a collection of Li-Ion packs?
Of course if you think I'm a mad scientist who must be stopped at all costs, please feel free to chime in too. Just stand over there on the scorched X on the floor next to the death ray...

Hmmm if the kernel allows for a charge higher than the one its in now. Like the evo charging issue with extended battery
Sent from my PC36100 using XDA App

BrianDigital said:
Hmmm if the kernel allows for a charge higher than the one its in now. Like the evo charging issue with extended battery
Sent from my PC36100 using XDA App
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Don't believe I've heard of this. Whassat?

loganthered said:
Don't believe I've heard of this. Whassat?
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Like he said: Whaa? I had an EVO [fun] but couldn't stand the less than less-than-stellar battery life. I'm talking dead by 4pm crap. Bought an extended battery and noticed no improvement. Is that why? Finally downgraded to an EVO shi[f]t [less fun] but I'm not getting the kind of improvement I would've expected going from a 4.6 to 3.6 inch screen, after all aren't they the biggest battery sucks?

sounds too scary for me!!! I think I'd rather just replace the battery (if it is possible to purchase one...)

The main issues would be....
1. extra strain on the charging circuit.
2. the possibility of battery imbalance...leading to extra strain on charging circuits...possible overheat...boom
3. possibility of overheating due to combined heat from 2 batteries during heavy charging...boom.
make sure all of those are taken care of and you are golden. Personally, I would source a larger amperage battery with similar dimensions and wire it in.

I like the idea, carry on

Why not just charge thru USB? Car adapter or external power pack?

UCSB said:
Why not just charge thru USB? Car adapter or external power pack?
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Because that defeats the purpose of bringing it a long for camping ;p or being marooned on an island with a black fog monster and a bunch of other idiots.

Just get the Energizer XP8000 and a little duct tape and you can get about 10+ extra hours out of it.

ExploreMN said:
Just get the Energizer XP8000 and a little duct tape and you can get about 10+ extra hours out of it.
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Which model do you recommend?

Duck brand duct tape is pretty good
Gorilla works well too

ExploreMN said:
Just get the Energizer XP8000 and a little duct tape and you can get about 10+ extra hours out of it.
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I have one of those, and yes it will charge the Nook Color on the go.

Just a little heads up on the topic, android stores battery info in the boot partition I believe and that's what tells the kernal the status of the battery, I.e. a double capacity battery would report as fully charged when only half charged if you didn't Pachelhoffer the is/kernal and such to match the new capacity.
Correct me if I'm wrong!
Sent from my NookColor using Tapatalk

use external battery pack
deadbot1 said:
The main issues would be....
1. extra strain on the charging circuit.
2. the possibility of battery imbalance...leading to extra strain on charging circuits...possible overheat...boom
3. possibility of overheating due to combined heat from 2 batteries during heavy charging...boom.
make sure all of those are taken care of and you are golden. Personally, I would source a larger amperage battery with similar dimensions and wire it in.
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These are excellent points. I would avoid hacking the internal circuitry and instead get a hold of an external battery, design a circuit to drop the voltage to 5v and use the usb cable to charge up the battery. Trying to charge two batteries in parallel is asking for trouble because of the imbalance problem.

d.v said:
Which model do you recommend?
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For the price, I got the XP1000 I think (its in my backpack which I left at work) I actually got it for my Epic to charge when I was out and about and moved around too much to use a wall charger. Works on the Nook too, but I haven't tried a real charge to see how much I get out of it. I would guess if I can charge my Epic 2-3 times that I could at least recharge the Nook once completely.

Warning - be careful screwing around with the internal LIPO battery and circuits. If something damages the single cell battery or voltage gets to low, and you try to add voltage and amps to it, it might puff up and if it does its flammable!
Its a single cell LIPO pack like used in rc airplanes and cars! They are very finicky to say the least when it comes to discharging and charging. Let alone if you want to hook up another one to it and do it wrongly! People have burnt down there whole house at night just over charging one and not babysitting the charging progress!
It is a lithium-polymer battery and not a lithium-ion!
They can catch fire when they puff instantly, many videos on youtube!

Correct me if im wrong, but the battery has a built in monitor and charge stopper so if you were to charge both the batterys via the micro usb slot you would need some sort of trickle charge/sbc kernel mod to overcome this which could be a real pain in the arse and not to mention dangerous considering trickle charge has been known to damage batteries on occasion and we do not have an easily replaceable battery.

I have this unit, http://www.amazon.com/gp/product/B0038VQET4. It will completely charge the battery of the nook.

jerrykur said:
I have this unit, http://www.amazon.com/gp/product/B0038VQET4. It will completely charge the battery of the nook.
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And a lot of other things, I'd gather, judging by the number of "tips" it comes with.
Do you have any idea if it will charge an NC more than once?

Battery question mark on boot

http://imgur.com/OxMh838
I just replaced my battery in the Droid 4, since my previous battery swelled up and started leaking. Motorola said they would cover it, even if it was out of the warranty, but they returned my phone with the battery ripped off, saying that "user mistreatment" was the reason they couldn't uphold their promise.
So, I installed a new battery from Amazon, and this is the issue that I get.
I was able to get into Android for a while, but after the charge died, this is all I get. I've tried quite a few things to be able to flash, anything, but no luck.
Any ideas out there? :/

I've seen that with a duff battery (broken connections) - I'd get a replacement, and see if that cures the problem.
Cheers,
Steve

StevePritchard said:
I've seen that with a duff battery (broken connections) - I'd get a replacement, and see if that cures the problem.
Cheers,
Steve
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Heh, well this is the replacement battery. Was hoping a brand new one wouldn't be broken, and don't really feel like spending another 35 bucks on this phone. Guess it's time to trash it. Thanks man.

AKARaccoon said:
Heh, well this is the replacement battery. Was hoping a brand new one wouldn't be broken, and don't really feel like spending another 35 bucks on this phone. Guess it's time to trash it. Thanks man.
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If you are seeing that on both batteries, then I would check the connections on the phone. Between the two screw battery terminals, there are a couple of connectors that stick up - gently give them a scrape with something abrasive. If there is some dirt of corrosion on there, then it may be possible that they aren't making good contact with the terminals on the battery cable.

StevePritchard said:
If you are seeing that on both batteries, then I would check the connections on the phone. Between the two screw battery terminals, there are a couple of connectors that stick up - gently give them a scrape with something abrasive. If there is some dirt of corrosion on there, then it may be possible that they aren't making good contact with the terminals on the battery cable.
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Gonna ask a stupid question.
Do the screws need to be in for it to actually register a battery?

AKARaccoon said:
Gonna ask a stupid question.
Do the screws need to be in for it to actually register a battery?
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I would say so, as the screws are part of the power contacts, and also ensure that pressure is applied to the data contacts.

StevePritchard said:
I would say so, as the screws are part of the power contacts, and also ensure that pressure is applied to the data contacts.
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I don't understand why it would work for one day, then stop working once the power is drained. Would that not mean the contacts are connecting?

Did you fix your phone? i have same issue, i have clean connectors but i have not success

[Q] When is Zerolemon extended battery for Samsung Galaxy S 4 Active coming out?

I would like to know When is Zerolemon extended battery for Samsung Galaxy S 4 Active coming out?

Never. That would require a new battery cover which is very accurately designed with it's o-ring to seal out water from Samsung. Do you want to trust a $600 device to a cheap 3rd party cover designed by some wanna-be engineer that it's going to hold 30 minutes at 1 meter?

Questions and help issues go in Q&A and Help section
Thread moved
Thanks
FNSM

Probably never. This isn't a dumb question like the guy above made it seem. They would just release a battery with a case that would devoid the protection that the device receives from the back cover. Which still wouldn't be too bad, considering you'd still have the shock proof, dust proof, and "water resistant" front (I say that, because now the back isn't). It also probably won't ever come out, because very seldom few people like you and I would like a huge battery for the Active, as the only way to do that would really be to lose water proof capabilities. Which is the main reason why people got the phone. So, it's just not a money maker if they did. They might sell ten or maybe even 100, but not enough to spend the money to develop it and produce it.

One of the other advantages of the S4Active is that it has a removable battery. What I do is, I have a second battery which I bought along with a charging pack that charges the battery independent of the phone. It was the best investment I've made in regards to phone accessories so far.
This way, I always have a second battery that I can carry around with me (in a secure little case) without sacrificing the size/aesthetic of the phone (since I can put that spare in another pocket, leave it in the car, etc) and I don't have to worry about the water proof seal. In addition to this, I'll use the MHL port a LOT less, which means I'm far less likely to damage it (or it's flimsy water-proof cover).

tiskael said:
One of the other advantages of the S4Active is that it has a removable battery. What I do is, I have a second battery which I bought along with a charging pack that charges the battery independent of the phone. It was the best investment I've made in regards to phone accessories so far.
This way, I always have a second battery that I can carry around with me (in a secure little case) without sacrificing the size/aesthetic of the phone (since I can put that spare in another pocket, leave it in the car, etc) and I don't have to worry about the water proof seal. In addition to this, I'll use the MHL port a LOT less, which means I'm far less likely to damage it (or it's flimsy water-proof cover).
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I think I'll follow the suggestion of having a separate battery charge and an extra battery pack.

Magnets and Li Batteries

Is there an actual harmful effect on a Li battery caused by the magnet in a leather case?
I have a leather case for my Z1 and I want to use it but I won't use it if the magnet in the lock is going to knacker the non removable battery.
Sent using my Z1 & Tapatalk 2 and not that abortion of a XDA premium app that I paid for and now shames the community it serves.....

The active ingredients in a Li-Ion battery are Lithium and Carbon. Lithium itself is an alkali metal, and is not magnetic, therefor adding a magnetic charge to it will not do anything. The Carbon inside a Li-Ion battery is Propylene carbonate, which is an organic carbon mixture, and is classified under low grade magnetic field. This means that any consumer grade magnet won't affect it.
If you're near high powered chemical magnets or industrial applications of magnets for scientific testing, then you may have an issue, however most laboratories don't allow electronic devices inside a controlled environment.
Any Neodymium magnet you throw at your phone, those are the silver, powerful "rare earth" magnets, or lesser powerful magnet found in most fridge magnets and wallets/cases, won't affect your phone in a negative way.
Source: I'm a scientist.

Wiltron said:
Source: I'm a scientist.
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I am glad the source is reliable but the phone it self contains metal parts and use magnets around can influence the phone reception and even if this is not harmful to my phone I will avoid magnetic contact anyway.

eclyptos said:
I am glad the source is reliable but the phone it self contains metal parts and use magnets around can influence the phone reception and even if this is not harmful to my phone I will avoid magnetic contact anyway.
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His question was about the battery.. not the other parts of the phone.
Even still, the phone is magnetically shielded.
Unless you're around extremely powerful magnets, such as working in science labs and/or electromagnets in junk yards, you don't need to worry about the tiny extremely weak magnet in the case.

Wiltron said:
His question was about the battery.. not the other parts of the phone.
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It not make difference.
Wiltron said:
Unless you're around extremely powerful magnets, such as working in science labs and/or electromagnets in junk yards, you don't need to worry about the tiny extremely weak magnet in the case.
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What about LCD? I got bad experience with a small magnet, it can damage the screen.

eclyptos said:
What about LCD? I got bad experience with a small magnet, it can damage the screen.
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Again.. he is not asking about the LCD.. he is asking about the Battery.
LCD screens are not affected by any source of magnetism either. If they were then cases like these wouldn't be on the market.
Things like these also wouldn't be backed by large companies or be so successful:
http://www.niteize.com/product/Steelie-Car-Mount-Kit.asp
https://www.kickstarter.com/projects/studioproper/wallee-m-modular-magnetic-phone-mounting-system
Lets not forget that the phone itself has a magnet on the side of the device and a smaller magnet on the cable for the magnetic charging port. If you know anything about physics you'll know a current runs through the USB cable when it's charging the phone, which also doesn't affect it.
Holding a magnet up to an unshielded SnapDragon or whatever, or the mainboard, then yes, but these phones have aluminium shielding.

I don't really mean to revive an old thread, but I'm about to attach some rare earth magnets to my ravpower QI charger with an external battery. I'm assuming my external battery is lithium-ion based. I want to spread out the magnets so my phone can properly attach to it, but I wanted to make sure everything is fine first.
I googled another forum that explained that using magnets with lithium ion cells can potentially cause a dead-short.
"side impact will cause magnet to shift and possibly bridge to ground causing a dead short. a very bad thing to do with a li-ion cell. this could lead to venting with flames!"

Mophie LG G4 Juice pack test results

Here is a link for a test on bandwidth and RF differences with Mophie battery case for the G4 as compared to no case and a clear lion case:
http://s4gru.com/index.php?/topic/6832-lg-g4-user-thread-was-rumor-thread/page-16
(would have reported it here but was having difficulty getting the charts to display in reasonable form.)

dyeager said:
Here is a link for a test on bandwidth and RF differences with Mophie battery case for the G4 as compared to no case and a clear lion case:
http://s4gru.com/index.php?/topic/6832-lg-g4-user-thread-was-rumor-thread/page-16
(would have reported it here but was having difficulty getting the charts to display in reasonable form.)
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The case battery is horrible. No way this gives 80% more and it heats the phone up a lot. was told by mophie that I should use case when phone is not in use. I dislike the fact that it is slippery. they need to step up the game.
BAD ASS NOTE 4 & LG G4

Only 450 mAh more than stock? Why would I want a bulkier phone for that?

flamadiddle said:
Only 450 mAh more than stock? Why would I want a bulkier phone for that?
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I'm not sure about your math. The mophie has a 3450 mAh battery, so that would be a full 3450 MORE than the internal battery. Since it is an external battery and all.
Also, I have had zero issues with my Mophie. No heating issues or signal issues. FWIW.

spongers said:
I'm not sure about your math. The mophie has a 3450 mAh battery, so that would be a full 3450 MORE than the internal battery. Since it is an external battery and all.
Also, I have had zero issues with my Mophie. No heating issues or signal issues. FWIW.
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D'oh, I was thinking it replaced the stock battery. That makes a lot more sense now.

Why would you waste your money on this piece of crap? Maybe for the s6 or iPhone. But we have removeable batteries that's the whole point. You could've easily got 2 maybe even 3 batteries for the price of that case.
1. Not wait for a charge
2. Not causing additional heat
3. Keep it slim.

bodom_hc said:
Why would you waste your money on this piece of crap? Maybe for the s6 or iPhone. But we have removeable batteries that's the whole point. You could've easily got 2 maybe even 3 batteries for the price of that case.
1. Not wait for a charge
2. Not causing additional heat
3. Keep it slim.
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Why would you post such a crappy post without actually trying the product? First off, extra batteries are nice and all but you actually have to turn the phone off to replace the battery, that's a waste of time. Secondly, how would you know it causes additional heat? Mine doesn't and I use it everyday. And guess what? I can charge the phone and the battery pack with one cable, all at the same time.
To each his own, so maybe you should bite your tounge and not post such blatantly blasphemous posts and let others form their own opinions.

My second case going back for a refund. rather have a good quality case and battery in pocket then a slippery phone that one day would end up breaking.
BAD ASS NOTE 4 & LG G4

To my surprise, I have not had heat issues with the g4 with or without the Mophie case, even when doing more than on my G2, which did have overheating issues. I agree that the Mophie should have more texture for a better grip on this case.

Proper comparison cost wise is an extra battery and a case since Mophie supplies both. I did find the case very easy to remove, although I would always keep it on. I do like the sound being redirected to the front.
I measured signal because many wireless charger backs have been shown to dramatically affect performance. In the FCC documents, most manufacturers are no longer releasing their antenna diagrams. If you have signal issues with the Mophie juice pack case, hold it vertical.
I have found that a 2.4 car charger is not enough for the LG G4 (I swapped charges and USB cable as well), nor can the Mophie case make up that power difference. However this excessive power situation was resolved by reducing the number of active apps by one and rebooting to kill a runaway Google service.
I did consider extended batteries, but then you must go caseless to the best of my knowledge.
With the replacement batteries you must also remember to carry them and you risk breaking the back cover with repeated use.
It really depends on how often you need extra battery power as to whether the Mophie case is worth it, plus the caveats and benefits listed above by all.

spongers said:
Why would you post such a crappy post without actually trying the product? First off, extra batteries are nice and all but you actually have to turn the phone off to replace the battery, that's a waste of time. Secondly, how would you know it causes additional heat? Mine doesn't and I use it everyday. And guess what? I can charge the phone and the battery pack with one cable, all at the same time.
To each his own, so maybe you should bite your tounge and not post such blatantly blasphemous posts and let others form their own opinions.
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Agreed with other guy.
Battery case is not optimal. Basically this battery is charging the OEM internal battery.... constantly.... which will end up killing your OEM battery.
The best solution would be to remove the OEM battery and replace it with a 6000mAh battery/custom backplate that snaps on.
Hence why these are causing the phones to heat up.

player911 said:
Agreed with other guy.
Battery case is not optimal. Basically this battery is charging the OEM internal battery.... constantly.... which will end up killing your OEM battery.
The best solution would be to remove the OEM battery and replace it with a 6000mAh battery/custom backplate that snaps on.
Hence why these are causing the phones to heat up.
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Except you're wrong. This case has a switch which the user controls. The switch dictates whether the case is charging the phone or not. So when you don't need it, its not charging, and thus not heating up the phone.
Again, if you actually have used the case before you would know this.

I just picked up this case yesterday and I really like it. Although the material is a tad slippery, the finish is a bit softer than normal plastic covers so it does feel pretty nice in my hand. Super bulky but I did come from a Nexus 6 so I don't mind and the reroute on the speakers to the front is pretty cool too as that was something I missed from my Nexus.

player911 said:
Battery case is not optimal. Basically this battery is charging the OEM internal battery.... constantly.... which will end up killing your OEM battery.
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Right, this is what typically kills laptop batteries much before their time. That constant charging.
player911 said:
The best solution would be to remove the OEM battery and replace it with a 6000mAh battery/custom backplate that snaps on.
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That is what i thought was going on. replace the original with an extended. Nope.
Instead they are treating this thing as if it has a non-removable battery. Bad design.
---------- Post added at 10:20 PM ---------- Previous post was at 10:19 PM ----------
spongers said:
Except you're wrong. This case has a switch which the user controls. The switch dictates whether the case is charging the phone or not. So when you don't need it, its not charging, and thus not heating up the phone.
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How often you do that per day ?
this is more of a hassle than replacing the battery.

One Twelve said:
Right, this is what typically kills laptop batteries much before their time. That constant charging.
That is what i thought was going on. replace the original with an extended. Nope.
Instead they are treating this thing as if it has a non-removable battery. Bad design.
---------- Post added at 10:20 PM ---------- Previous post was at 10:19 PM ----------
How often you do that per day ?
this is more of a hassle than replacing the battery.
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Really? Sliding a switch is more of a hassle than powering off your phone, replacing the battery and waiting for it to boot back up? Your definition of hassle is WAY different than mine.
I only have to do this once a day, when my battery gets down to around 30%, and it charges it up all the way and has about 40% left on the external battery itself.
Again I say, how do you know it is a hassle if you haven't actually tried it?

This juice pack case is for travel use mostly. Hiking or cruising low signal is the one that drain the battery the most.
People who complain this is an impractical item without owning don't really understand who needs it. Sure you can swap batteries since this device has removable back to replace batteries. But what if you are on important phone call? Or got lost somewhere where you can't really stop the vehicle but battery is going low and don't have the time to stop/shutdown/replace battery/ turn on/ open apps? What if you are in time constrain situation (emergencies) that you must keep your phone alive? This juice pack can offer that quick and simple just by switching on.
Sure external battery does it exactly the same with far less price, but the convenience make up for the price. I cant really justify with the $99 but a case that with built in battery? Some might think it's a good price.
Sorry for the long post.
Sent from my LG-H811 using XDA Free mobile app

spongers said:
Really? Sliding a switch is more of a hassle than powering off your phone, replacing the battery and waiting for it to boot back up? Your definition of hassle is WAY different than mine.
I only have to do this once a day, when my battery gets down to around 30%, and it charges it up all the way and has about 40% left on the external battery itself.
Again I say, how do you know it is a hassle if you haven't actually tried it?
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How do you know a broken leg gives you a hard time walking, if you never had it broken? The answer - common sense. In other words, your arguments aren't really that.
This case is useless for everyday use, compared to an extra battery. Instead of using a slick phone with a nice size/screen size ratio, it turns it into an awkward brick. Ok I understand using it occasionally while traveling, like an external battery if you don't wanna take your back off...
Still don't get it though why they make these for phones with removable batteries..

0rigin said:
How do you know a broken leg gives you a hard time walking, if you never had it broken? The answer - common sense. In other words, your arguments aren't really that.
This case is useless for everyday use, compared to an extra battery. Instead of using a slick phone with a nice size/screen size ratio, it turns it into an awkward brick. Ok I understand using it occasionally while traveling, like an external battery if you don't wanna take your back off...
Still don't get it though why they make these for phones with removable batteries..
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Your logic is absolutely baffling to me. But whatever, to each is own. All I am saying is don't bash something you haven't tried. You have no clue what you are talking about, and it makes you look unintelligent.

sharpehenry said:
This juice pack case is for travel use mostly. Hiking or cruising low signal is the one that drain the battery the most.
People who complain this is an impractical item without owning don't really understand who needs it. Sure you can swap batteries since this device has removable back to replace batteries. But what if you are on important phone call? Or got lost somewhere where you can't really stop the vehicle but battery is going low and don't have the time to stop/shutdown/replace battery/ turn on/ open apps? What if you are in time constrain situation (emergencies) that you must keep your phone alive? This juice pack can offer that quick and simple just by switching on.
Sure external battery does it exactly the same with far less price, but the convenience make up for the price. I cant really justify with the $99 but a case that with built in battery? Some might think it's a good price.
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ok so that is the use case this is specfically designed for.
Sorry for the long post.
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Never apologise for that
---------- Post added at 03:14 AM ---------- Previous post was at 03:12 AM ----------
0rigin said:
This case is useless for everyday use, compared to an extra battery. Instead of using a slick phone with a nice size/screen size ratio, it turns it into an awkward brick. Ok I understand using it occasionally while traveling, like an external battery if you don't wanna take your back off...
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And that is the use case i amongst others are looking at it from.
Still don't get it though why they make these for phones with removable batteries..
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always on. if you don't need that then this isn't the right product.

Just picked up one of these from the AT&T store because they had cleared them out for $10.
Anyway, it seems good so far, and the textured rubber/plastic material seems like a good grip.
Also this battery pack is great for me, because I play this game called Ingress and when you are with groups you quickly walk from one GPS location to the next, and you are constantly needing to take actions on the phone, so you don't have any opportunity to actually shut down your phone for a battery swap. I think external battery augmentation, like this mophie provides, is perfect for playing Ingress on walk-about missions with groups.
And as Spongers so valiantly tried to point out above, yes there is a nice easy to use switch that lets you keep the battery pack off while you use the phone's internal battery, and then easily just flick the switch to turn on the mophie to recharge your phone. Mophie even helpfully points out in the instructions that this technique optimizes overall battery life between the mophie and the phone, because you spend only half the time recharging (total time split between draining only the phone's battery with mophie off, then draining the mophie after turning it on after phone's battery is low), instead of the entire time (where you would keep the mophie turned on all the time, generate more recharging phone heat/waste during the entire drains of both batteries).
Anyway, yeah I like it. Check if your local AT&T stores have any in stock, because it's a steal at $10. My store only had one left, or I would have bought all of them.