Lithium 3.7 Volt Battery

[tllim]

I was wondering if we use 3.7V Li Battery , then
1. will pine64 charge it once pine64 is connected to a usb power source such as computer or power bank?
1.1 if so, is there a build-ii overchage protection  in pine64?

Pine A64 will charge the 3.7V Li battery, there is overcharge protection circuit.

[Fr0z7y]

i decided to make my own battery box for this setup, i still need to get the 3 prong piece i saw someone post earlier in the thread, and the battery overheat fuse things between each battery just in case for the battery circuit box. anyways, what i am planning on doing though is to take 3 of the four battery slots and use those in parallel to have 9600 mah, while i have a usb hub on battery power from the fourth slot using an old circuit for a different single celled 18650 battery pack. although yes i could probably use all four of them in parallel on this pack, i don't believe i would be able to power the usb hub with all the devices hooked up to it, and the pine64 properly running at full tilt. i'll use a regular rocker switch or something to cut between the circuit on the usb hub for a custom box and what not im going to make, paint, and polish but that's a different thread.


for the powered portion of this, basically the part that has the led readout for the remaining battery portion is for a 4 pack of 18650 batteries inside a case that would fit it also sold on ebay elsewhere in a kit that's like 10$ usd, so the battery drain on this will reach the 2 amp threshold giving it about 4.2 hours or so with these batteries. the reason i picked these toosell batteries is because i bought the green ones that are only 2600 mah and have used them to great effect already in other projects including charging my tablet and phone with them, so i know these are not only good for phones, but they have a low discharge rate on them meaning they are less likely to heat up as they are being used or charged (although accidents can and do happen in any manufacturing process or other conditions).

i feel this will give me quite a good length of play on this machine, given that i bought 8 of them, i can swap them out when it runs low after about 4 hours running it playing high intensity games. hopefully this would allow me to play something like league of legends or dota 2 or some other game that i can run at extremely low settings while on the go or at a parents house or something (if that's even possible for those two games, but at least you know what i mean by full tilt)


the batteries. i have used the 2600 mah green ones, they fit any other thing that would require an 18650 as being a flat top does not affect the placement of the batteries at all, these are 3200mah
http://www.ebay.com/itm/141460652616
the battery box, you could pay more for ones to show up sooner, but i bought the one shipping in march soooo and i needed my own wiring scheme
http://www.ebay.com/itm/151681864358
this has one port for 5v 2.1a (tablet) and one for 5v 1a (most phones or could double as your usb hub power port) don't know if it can put out 3.1a total which is why i bought the previous item battery box and am using a old battery charger circuit board for the usb hub to power it
http://www.ebay.com/itm/231371589575


i hope this helps you guys, as those other batteries would work if they had enough output juice for the dollar, but to be honest you can basically use any portable battery that outputs 2.1a at 5v that you can buy from china for cheap or whatever, just don't expect to get a ton of juice from it for too long. you get what you pay for (except in this case this machine is awesome, the pine64)

i did spring for the 29$ pine64+ so it's basically a laptop but gimped a bit because of the ARM and other small things.

[paulieg]

I am a big fan of ebay. However, there are a few things that are not worth buying as ebay noname wonders. Batteries are one of them (for demanding applications). The ones you linked do not list ratings and, even if they did, I would not believe them. Very few li-ion batteries are rated to the specs required to run them in your proposed configuration, the defunct Sony ones for example, and these are nowhere near them. It's not a technology that's easy to knock off.

-p

[Fr0z7y]

I am a big fan of ebay. However, there are a few things that are not worth buying as ebay noname wonders. Batteries are one of them (for demanding applications). The ones you linked do not list ratings and, even if they did, I would not believe them. Very few li-ion batteries are rated to the specs required to run them in your proposed configuration, the defunct Sony ones for example, and these are nowhere near them. It's not a technology that's easy to knock off.

-p

the reason i picked these specific batteries is because i have also visited their website (although there is some misprint on it) i have also been using these batteries like i said, for quite some time now for charging my tablet and phone on the go.

what do you mean by ratings?  do you mean discharge of amperage? when you are place 3 or 4 of these in parallel that increases the output amperage. when you are dealing with battery discharge, especially this kind, using the other parts i have listed there, the output rating isn't truly necessary. but if you want to know what the output of the green one's i have in my hand are, let me grab my multimeter really quick and tell you.

3.64v 3.12a 2600mah

although now they have them both on their site listed as 3000mah batteries pink and green, so the one's that are being sold now are probably a earlier batch.

i understand your misgivings into buying a brand you don't know, but it's not necessary that you said this, that's fine if you don't want to buy these specific batteries, this was an example of how to build a very high mah battery for pretty cheap. the reason i say cheap is because you can find cheaper batteries out there that are the 18650's to use, considering that you can always swap them out like some aa size batteries in other electronics and charge them later with a wall charger, or when you get home or near a wall outlet, you can use the other part here i listed that has the input power to charge up all of those batteries using a different outlet to still use the pine64 on while the batteries charge.

these batteries can also be used in the other 18650 battery holders that they have on ebay or amazon, or wherever for that matter, and use them to charge your cell phone, or whatever. instead of having one battery that is only for your pine64, it can then be used in other applications, mitigating the cost some so it can be multipurpose.

that's all i was saying to begin with.

EDIT: the reason they are low on voltage atm, is because i have been using them and they are not fully charged right now, i was using them in another project i have going for something else running a pump and some fans off of two of them through a 5v regulator drawing like .6 amps for a little while. the part that has the led on it, that is basically the voltage and amperage regulation portion. it will step the voltage up to 5v and keep the amperage at a nice even 2.1 amps output through the usb cable into the pine64. the batteries you can buy anywhere. i just showed you the batteries i bought.

[paulieg]

I was not commenting on your setup as a whole, although there are comments to be made - balancing may be desirable or mandatory for safety depending on the exact chemistry your 18650 uses (18650 is a form factor, not a chemistry specification), likewise with protection - protection is hard to do properly if you don't have the discharge curves and with cheap no-name batteries you never do. I was simply stating that buying el-cheapo batteries is invariably a bad idea for high discharge applications. Depending on the exact chemistry used, it may not be a fire risk but you might have brownouts or considerably shorter lifespan that makes these batteries more expensive than higher quality, well-branded ones. There's a huge amount of information online about this subject, so it's a bit pointless to rewrite it here. Suffice to say that certain communities like vapers (batteries powering atomizers) and flashlighters have done a huge amount of extensive testing on this, the upshot being that you have every opportunity to use their data to select appropriate batteries.

As a matter of simple math, generic chinese 18650s sold as 3000mAh usually turn out to be in the region of 1000mAh. Since they're usually only capable of 1-1.5C and the curve stops delivering much earlier, you're starting to butt up against it if you place a 2+A load on them. Since you're now running them harder and out of balance as well, chances are you're killing the lifespan and total capacity, screwing the curve even more (although I'm not sure if reduced capacity affects C rating for all chemistries - you need to check datasheets).

This isn't a dig at you and I think people posting their DIY projects and results is awesome. I'm sure people will find yours useful. I'm just pointing out that, in the case of batteries for high discharge applications, paying for quality ends up being cheaper in the medium to long term, safer and considerably more hassle-free.

-p

[Fr0z7y]

I was not commenting on your setup as a whole, although there are comments to be made - balancing may be desirable or mandatory for safety depending on the exact chemistry your 18650 uses (18650 is a form factor, not a chemistry specification), likewise with protection - protection is hard to do properly if you don't have the discharge curves and with cheap no-name batteries you never do. I was simply stating that buying el-cheapo batteries is invariably a bad idea for high discharge applications. Depending on the exact chemistry used, it may not be a fire risk but you might have brownouts or considerably shorter lifespan that makes these batteries more expensive than higher quality, well-branded ones. There's a huge amount of information online about this subject, so it's a bit pointless to rewrite it here. Suffice to say that certain communities like vapers (batteries powering atomizers) and flashlighters have done a huge amount of extensive testing on this, the upshot being that you have every opportunity to use their data to select appropriate batteries.

As a matter of simple math, generic chinese 18650s sold as 3000mAh usually turn out to be in the region of 1000mAh. Since they're usually only capable of 1-1.5C and the curve stops delivering much earlier, you're starting to butt up against it if you place a 2+A load on them. Since you're now running them harder and out of balance as well, chances are you're killing the lifespan and total capacity, screwing the curve even more (although I'm not sure if reduced capacity affects C rating for all chemistries - you need to check datasheets).

This isn't a dig at you and I think people posting their DIY projects and results is awesome. I'm sure people will find yours useful. I'm just pointing out that, in the case of batteries for high discharge applications, paying for quality ends up being cheaper in the medium to long term, safer and considerably more hassle-free.

-p

yes, i know, i did that research before i bought these from ebay. these aren't exactly "cheap" batteries. they aren't a "major" brand. i saw how many knockoffs there were and what brands to stay away from. in this specific application that i am using, there already is a protection circuit in play with the part that connects directly to the 18650's, which is the third part i listed.

your concerns about the 18650's with chemistry, voltage, amperage discharge, capacity, pretty much all of that, i have checked before i ever bought these in the first place. because there were a lot of batteries out there and the amount of batteries that people have been labeling as something else (like you are stating that they have different capacities than stated and what not, all of your concerns) i basically found a brand that looked solid. i tested it already to great lengths, and thats why i listed these for you guys.

the reason i do not usually buy from say, bestbuy, walmart, or amazon, is because they usually list products at 3 times the price they bought them for or with amazon they buy it from ebay and resell them for a hefty markup and they are the same thing you find on ebay.

each person i listed also has many transactions on record with a 98.5+ rating (given the amount of sales done already and knowing how some people will just leave negative feedback when it was their own fault) i listed those and bought those because i also know i am dealing with a piece of hardware that needed voltage/amperage protection and a steady stream of juice.

if im willing to use these on a 250$ almost irreplaceable tablet (due to the things i have on it and the funds available) i think it would be okay to hook it up to a 35$ mini computer through a very well put together protection circuit with a battery readout.

the chemistry of the batteries are lithium ion. if you do a quick search on ebay for toosell 18650, you will see the number of sellers that have them listed. if you do a search on google regarding them you will also see what im talking about there.

but aside from the batteries i listed, lets move onto the protection circuit i have posted here. that is for both usb charging for the 18650 lithium ion batteries and will protect the pine64 from overvoltage and overamperage. the circuit board there will allow you to use the same usb cable that you are using to plug into the pine64 to power it as you do to charge the batteries by simply using a regular tablet charger.

other similar batteries as the flat wide long batteries with built in circuit for this will cost about 20$ for about 7000mah give or take 5 or 6$. if you just want to buy a battery that's all in one that will just plug into it and charge it without having to go and build this like i am, you can buy it for about 25-30$ already put together, and it's also going to have about 4 of these 18650's in it, with basically the same circuit, in a case, you can also use it for a tablet/phone with i think about 10000mah give or take about 4000mah depending on who you buy it from and the brand of battery pack.

considering this is an SoC that we are all building and having fun putting together as well as making things to use for it, i decided to give you an idea on how to put together a battery pack that will be a bit fun to put together, no matter what batteries you use ( i do believe you can put an elongated flat battery hooked up to this if you really want to, although its made for the 18650 style batteries)

if you have a different suggestion regarding a battery pack, i'ld like to know your setup you plan on utilizing, with a parts list you plan to use, if you do plan on using one instead of a tablet charger (which provides 2.1a at 5v and is suitable to charge expensive tablets and phones).

[paulieg]

-- snip technical arguments ---

You seem determined to take the technical arguments I am making as a personal affront. Please don't. Firstly, it's not productive. Secondly, it's not congruent with the spirit in which I make them. Thirdly, I've already stated multiple times that I applaud you for taking the time to share your DIY project with the community.

All I've done is made a case for buying quality batteries because they are safer, perform better and end up costing less in the long run when used for demanding applications. I've supported that thesis with technical arguments to a degree which I consider sufficient. It is everyone's prerogative, including your own, to make their own choice based on the arguments presented. I do not intend to restate those arguments; the responses below are simply corrections to (largely technical) inaccuracies.

yes, i know, i did that research before i bought these from ebay. these aren't exactly "cheap" batteries. they aren't a "major" brand. i saw how many knockoffs there were and what brands to stay away from. in this specific application that i am using, there already is a protection circuit in play with the part that connects directly to the 18650's, which is the third part i listed.

This isn't a case of whether a brand is 'major' or not. Kingston is a 'major brand', but their sd cards are A- flash chips and controllers they buy from competitors. With batteries, there are companies that have the technology and manufacturing facilities to produce battery cells, from the high end (eg Pana, Sony, Samsung, LG) to mid-range and cheap (OEMs you're unlikely to have heard of). The more capable or safe chemistries like LiNiMnCoO2 are areas of active research and development and the big boys are the ones doing it - you're simply not going to get INR knockoffs that can compete at this moment in time. Additionally, the problem with no-name batteries is that no-one knows where the cells come from and what their performance is like. Even if you test some batteries from one batch and they're OK, there's every chance the next batch will be different because they've bought cells on the spot market, slapped a case and markings on them and sold them. There's simply no guarantee of consistency, which is why they don't publish datasheets (they don't have the data, they don't care and they wouldn't be able to guarantee conformance over time).

This isn't me making a case for buying Patek Philippe when a Seiko would tell the time just as well; it's me making a case for not buying a cat in a bag, because with batteries unless you know the specs and trust that every battery you buy conforms to them, you're losing money when you think you're saving it (for demanding applications at least). If not on performance and safety, then on lifetime.

your concerns about the 18650's with chemistry, voltage, amperage discharge, capacity, pretty much all of that, i have checked before i ever bought these in the first place. because there were a lot of batteries out there and the amount of batteries that people have been labeling as something else (like you are stating that they have different capacities than stated and what not, all of your concerns) i basically found a brand that looked solid. i tested it already to great lengths, and thats why i listed these for you guys.

I found no reference to tests done on 'Toosell' 18650s anywhere. The flashlighters don't buy them, nor do the vapers from what I can see. They certainly haven't tested them. You haven't done a capacity test either, otherwise you would've posted the numbers when I brought the question up, therefore the 'testing' you've done is subjective and anecdotal. Even had you done such a test, there's 0 guarantee that the cells in a 'Toosell' battery someone buys today are the same ones as in the ones you bought and tested. There's no incentive to maintain standards - if they sell a catastrophically bad batch that even people who buy these batteries recognize as such (eg because they're now homeless and have soot all over their faces), they can just start selling 'Threesell' batteries tomorrow.

the reason i do not usually buy from say, bestbuy, walmart, or amazon, is because they usually list products at 3 times the price they bought them for or with amazon they buy it from ebay and resell them for a hefty markup and they are the same thing you find on ebay.

I haven't bought anything from bestbuy or walmart in years and yes, they mark up their stock to make you pay for the privilege of going to a physical store and having the item in hand immediately. The idea that amazon itself buys anything off of ebay is laughable. Amazon does act as a platform for third party sellers and, yes, they can and do often charge an arm and a leg because plenty of people want to buy off amazon specifically because of prime, convenience etc - it's our responsibility to shop around and determine if we're getting the best deal. Amazon has a great line of Amazon-branded NiMh batteries they buy from an OEM and badge as Amazon Basics or something in that vein at a great price for example. I've just gotten a fantastic deal for genuine coin cell batteries from a third party seller on Amazon as well. As with any e-commerce platform, there are good and bad deals to be had.

each person i listed also has many transactions on record with a 98.5+ rating (given the amount of sales done already and knowing how some people will just leave negative feedback when it was their own fault) i listed those and bought those because i also know i am dealing with a piece of hardware that needed voltage/amperage protection and a steady stream of juice.

Very few people who have the means to test 18650s properly buy them off of ebay. Very few people who use 18650s for demanding applications buy them from ebay. Issues with many important characteristics such as usable lifetime surface well after the cut-off deadline for leaving feedback has passed. Simply stated, most people just want a rechargeable battery they can stick in a clock or a remote or something of that nature and, as long as it appears to work, they're satisfied. Given this, general feedback ratings in this case are not valid indicators of quality.

if im willing to use these on a 250$ almost irreplaceable tablet (due to the things i have on it and the funds available) i think it would be okay to hook it up to a 35$ mini computer through a very well put together protection circuit with a battery readout.

That's certainly your prerogative. In any case, there are few failure modes for batteries that would be likely to result in damage to a tablet. I never said no-name batteries would fry your tablet, I just said that they're very likely a false economy.

Notwithstanding the above, someone's willingness to risk something valuable on the performance of a particular engineering solution has no bearing on the soundness of said solution - technical facts are objective and not an exercise in popularity or a function of confidence. There was once a man who attached a lot of helium balloons to his lawn chair and used this contraption to fly himself like an airship. His willingness to risk his life does not validate his engineering solution.

the chemistry of the batteries are lithium ion. if you do a quick search on ebay for toosell 18650, you will see the number of sellers that have them listed. if you do a search on google regarding them you will also see what im talking about there.

Li-ion is a general classification that merely indicates that the charge is carried by lithium ions. Performance and safety considerations vary widely based on the chemistry used, which could be anything from LiCoO2 to LMnO to LiNiMnCoO2 etc. If we are to believe the markings on the batteries you linked, they're ICR which means a cobalt-based chemistry (LiCoO2).

There are plenty of cheap products by Chinese OEMs that are sold widely on the interwebs. Some are good or good enough, some are not. They're not being sold widely because they're good, they're sold widely because they're cheap and people buy them. More people buy Bieber albums than listen to Chopin, their relative merits are not a function of popularity.

other similar batteries as the flat wide long batteries with built in circuit for this will cost about 20$ for about 7000mah give or take 5 or 6$. if you just want to buy a battery that's all in one that will just plug into it and charge it without having to go and build this like i am, you can buy it for about 25-30$ already put together, and it's also going to have about 4 of these 18650's in it, with basically the same circuit, in a case, you can also use it for a tablet/phone with i think about 10000mah give or take about 4000mah depending on who you buy it from and the brand of battery pack.

The 'long flat' batteries could be multiple li-ion 18650s (in fact, some laptop batteries can be used to salvage 18650s from) or they could be lipos. Lipos need to be handled differently than most common li-ion chemistries, so be careful there.

considering this is an SoC that we are all building and having fun putting together as well as making things to use for it, i decided to give you an idea on how to put together a battery pack that will be a bit fun to put together, no matter what batteries you use ( i do believe you can put an elongated flat battery hooked up to this if you really want to, although its made for the 18650 style batteries)

if you have a different suggestion regarding a battery pack, i'ld like to know your setup you plan on utilizing, with a parts list you plan to use, if you do plan on using one instead of a tablet charger (which provides 2.1a at 5v and is suitable to charge expensive tablets and phones).

Again, I'm all for this sort of thing - doing stuff yourself, finding deals and putting one over on companies with ridiculous markups on their products. I suspect that's very much the spirit in which most people backed this project. I've merely made the argument that for demanding applications, buying batteries of known quality and fit for purpose *saves money* most of the time. The people whose hobbies center on demanding battery usage, such as flashlighters, vapers and RCers, have long established this to be the case with extensive testing - they love to save money, so they won't buy anything because of a brand - they buy certain brand+models because they deliver the best value.

As for my plans, I have no interest in running pine64 on battery power as of right now. If I did (and I may in future), I'd wait to see what it actually pulls under various conditions before I made any definite plans. My intuition is that lipos are more appropriate in the general case. If I wanted to use 18650s, I'd use IMR (LiMn2O4) or INR (LiNiMnCoO2) and would be prepared to pay the extra money for it.

-p

[psychedup]

This is an interesting thread. Sorry if I'm hijacking it, but my question is somewhat related...

If I purchase the "official" LiPo battery that is sold with the pine64, would it be practical to have the battery connected to the pine64 at the same time it is plugged into AC power, all the time? Or would that wear out the battery?

I'm hoping to use it as a server that is always on. So the norm would be that it runs on AC power, but if the power goes out then the battery would keep it alive for some length of time. Would that be practical with this type of setup?

Thanks,
Chris

[tllim]

This is an interesting thread. Sorry if I'm hijacking it, but my question is somewhat related...

If I purchase the "official" LiPo battery that is sold with the pine64, would it be practical to have the battery connected to the pine64 at the same time it is plugged into AC power, all the time? Or would that wear out the battery?

I'm hoping to use it as a server that is always on. So the norm would be that it runs on AC power, but if the power goes out then the battery would keep it alive for some length of time. Would that be practical with this type of setup?

Thanks,
Chris

The current configuration is similar to how LiPo battery connected to a tablet. If all time connected to power and battery just for loss power backup, I think the wear out should be minimum.  We currently has one developer working on Pine A64 PMIC and hopefully we will have better way to optimize the battery charging to serve server configuration enviroment.

... TL Lim

[UnixOutlaw]

I bought 4 x 3.7 v LiPO 2000Mh batteries - assuming they'd work on Pine64 (I bought them for CHIP originally - but hoped they'd be interchange-able)...  But connector is wrong.

It would be >NICE< if Pine could provide some part numbers for people OUTSIDE the USA to buy compatible batteries...

And I can't find any diagrams of which pins do what on the LiPO connector...  I'm assuming that the middle pin does nothing - or is GND ?