DIY cheap powerbank (technical suggestions R welcome !) - Page 1
Forum section: electronics / projects

author: ym58
author_rank: Regular Contributor
timestamp: August 03, 2016, 04:03:57 am
content: My bottom-line was to build a cheap but yet fully functional and powerful power bank using :- aPCBsalvaged from aChinese 2euro-powerbank-two LiPos(8.2Wh each) salvaged from adefective Sony Vaio battery packKind of suspicious association ... but let's try it:The final boxed prototype looks a bit like a trendy NYC designer's techno thingy O0 ...It works of course but there are two flaws breaking my initial rules :#1 it takes>12hrs to recharge its two LiPos(from a regular 2A wall charger)#2 theoutput current is limited to 1Aor so (making it less ***powerful*** that I had expected)The reason being (well, I suppose) that theFM9833Ethe salvaged PCB is based on is limited to0.6Afor the battery charging current and to1Afor the output current.I tried to lower theR3 resistor(down to 1K) in the hope that this could increase the battery charging current but to no avail.If anyone has any suggestion how to increase the battery charging current, please come back to me in this thread !If I can't improve this PCB "as it is", my next option will be to tryanother PCBlike this one that I have just ordered on eBay :Any suggestion is welcome !

author: qnh
author_rank: Newbie
timestamp: August 03, 2016, 11:51:58 am
content: Nice (and cheap) work ... sustainable economy!I just can't find info concerning the chip that you mentioned (FM9833E).Do you have any datasheet on your side. ?

author: JacquesBBB
author_rank: Frequent Contributor
timestamp: August 03, 2016, 01:36:32 pm
content: The problem with these boards is that usually you cannot charge the battery while you use it.I prefer a different setting withtwo very cheap boards- one for charging/ discharging the battery with protectionhttp://www.ebay.com/itm/5pcs-5V-1A-USB-18650-Lithium-Battery-Charging-Board-Charger-Module-Protection-/322045031371?hash=item4afb6133cb:g:RDUAAOSwRgJXigY4- a second one for providing the proper voltage as requested.It can be USBhttp://www.ebay.fr/itm/401089512266?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT- or a boost converter for higher voltage .they can be connected together in a very small package.total cost < 1$

author: ym58
author_rank: Regular Contributor
timestamp: August 03, 2016, 03:33:04 pm
content: Quote from: qnh on August 03, 2016, 11:51:58 amActually, the link was embedded in my previous post !Here again >>>FM9833E<<<Any technische Klärungwill be much appreciated.

author: ym58
author_rank: Regular Contributor
timestamp: August 03, 2016, 03:54:00 pm
content: Quote from: JacquesBBB on August 03, 2016, 01:36:32 pmHello Jacques,But that was none of my intentions !These so-called powerbanks are made to store energy from a wall charger and then to be able to transfer it back to charge any mobile device that might have run short of battery "on the road" ...In a powerbank, those two different functions (store then give-back) aremandatotybut yet notconcurrent(concomitant) !---The PCB I have salvaged does the job but does not really fullfill the charging requirement for two (2) parallel 8.2Wh-LiPos , i.e. aCC(constant current) around1C, that is about 2A per battery =4A total!The IC used on this board (FM9833E) can only deliver a mere 0.6A charging current to the 2 batteries, hence the extended duration of the charging process (>12hrs, instead of 3 to 4hrs at1C!)

author: qnh
author_rank: Newbie
timestamp: August 03, 2016, 04:58:31 pm
content: I looked at the .PDF you gave me for the FM9833E chip, but it's all in Chinese !!!I did not see much info relating to the charging current setting, the only thing that I undersatnd is that R1 - 2K (connects to pin4=PROG) may have a role in this ... but I don't know how !However, I might have found something interesting for your research, it can be found there :http://mysku.ru/blog/aliexpress/38446.htmlSorry, it's in Russian this time, but if you scroll down a bit, you will see that there is some info concerning the same chip as yhe one you use.Maybe someone here, speaking Russian, can help you ?

author: ym58
author_rank: Regular Contributor
timestamp: August 04, 2016, 07:32:24 am
content: Quote from: qnh on August 03, 2016, 04:58:31 pmI have Google-translated the Russian document and learned (well, as far as the Google translation is accurate) that theREcharging current, flowing from the FM9833E circuit to the battery(ies) can be decreased from 0.6A by ways of increasing the R1 pulldown resistor (connected to the PROG pin of the chip), but apparentlyNOT THE OTHER WAY ROUND---I think that FM9833E-based circuits won't fit my requirements, which are not so high (1A charging-CC per battery and 2A output current).I am not requesting a QC2.0* or QC3.0* compatible circuitry, just a basic QC1.0* would be satisfactoryHas anyone here got any clue ?* @Qualcomm Inc.

author: Ranger14
author_rank: Regular Contributor
timestamp: August 06, 2016, 02:20:19 am
content: See most Chinese use one chip wonder that not available in the US ... I am not sure if there are chips available in the US that charge and boost??? Power banks are a whole another beast when building one .. Most power banks run 18650 cells in parallel which most people recommend not doing.. Another issue is the charging current for the batteries. Most usb sockets can only output 500ma to 1amp and can't charge a single cell at 1c.The charging IC they use is only meant to charge a single 18650 cell at 1amp but they still use it to charge a battery bank.. Personal I can't a charge IC to charge parallel 18650 cells .. The list just keeps going on but can be done if you don't settle on certain specs..

author: ym58
author_rank: Regular Contributor
timestamp: August 06, 2016, 05:59:32 am
content: Quote from: Ranger14 on August 06, 2016, 02:20:19 amYeah, I've even seen cheap powerbanks claiming > 20000mAh capacity withFOUR(4) 16850 in parallel !The sky is our limitIn my case, I selectedTWO(2) 8.4Wh Lipos carefully ascertained to be compatible (same discharge capacity, same full charge voltage) before I can use them in parallel.Besides, those two batteries were already paired in the Sony Vaio Battery Pack that I salvaged for the need of that pick.Quote from: Ranger14 on August 06, 2016, 02:20:19 amYes, that's why I intended toREcharge my PowerBank prototype on strong wall sockets only (at least 1.5A/5v), but alas the limitation comes from the chip itself and not from the wall socket.I even used my lab power supply (5A max) during my tests for me to monitor voltage and current more easily and accurately than with that :---However, a right boost circuitry (with the correct inductor), would normally do the trick even from a 0.5A wall socket source.What's frustrating here is that this chip (FM9833E) can't output any charging current better than 0.6A ... even 2A would have made me happy (1A per battery) !

author: ym58
author_rank: Regular Contributor
timestamp: August 06, 2016, 06:06:18 am
content: Quote from: blueskull on August 06, 2016, 02:45:38 amThanks for the translation, Blueskull.---I think that you're right,the die is cast!I won't be able to draw anything better than0.6Afrom that chip.---Hoping that the next board (that's on its way from China) will be better on that point :---Do you have any info on that one ?

author: ym58
author_rank: Regular Contributor
timestamp: August 06, 2016, 12:55:40 pm
content: Actually, I just received this morning the new PCB from HK (via Istanbul !!!)---I am just quite upsetcoz it worked for 30min in discharge mode (one piece of fully charged Lipo connected to B+/B- and a 4R/100W resistor load connected to the USB-OUT 2.1A output).The LCD was then just working fine, with a nice'95%, 5V-2.1A'message (with percentage decreasing smoothly) and I effectively measured a 1.2A discharging current with my DC clamp ammeter ...Then, all of a sudden, it just stopped and nowit's deadand the LCD does not even light any more!I tried to reverse the process and charge another half-charged Lipo thru the microUSB, the LCD lights up correctly and gives a coherent percentage (57%, i.e. the charge state of the current LiPo) but actually it does not charge at all the battery, the current is near to zero ... no way, the PCB is dead !---Since I had ordered another one to another supplier, I must now wait another couple of days/weeks before I can resume my tests.---However, I made a pic of the dead PCB and indicated the chips references, just in case someone would got a clue whether this PCB (in working condition) could possibly charge LiPos with currents > 1A ... ?

author: edavid
author_rank: Super Contributor
timestamp: August 06, 2016, 03:06:41 pm
content: Why not charge each cell with a separate TP4056, and combine the outputs with some big Schottky diodes? You'll lose a little capacity that way, but at least it will work.

author: ym58
author_rank: Regular Contributor
timestamp: August 06, 2016, 04:26:35 pm
content: Quote from: edavid on August 06, 2016, 03:06:41 pmA TP4056-based circuit will only handle theCHARGEof the LiPos( or Li-Ions).What I want is a reversible circuit (exactly as those cheap ones described earlier in the thread) that can not onlyCHARGEbut also manage theDISCHARGING(with correlative protection) of the LiPos into the external load (smartphone, iPad, tablet ... you name it).Actually, I think they call this aBMS, for Battery Management System.---And also, my bottom line was to make a funny prototype with what already exists ans sells a few bucks, instead of designing something that will eventually cost more than a real 20000mAh LiPo-based powerbank (around 25€-35€) !

author: Kilrah
author_rank: Unknown
timestamp: August 06, 2016, 04:35:50 pm
content: Quote from: ym58 on August 06, 2016, 04:26:35 pmGood luck then, since I don't even actually know of any "real" powerbank that does what you want (charge at >1A).

author: ym58
author_rank: Regular Contributor
timestamp: August 06, 2016, 05:35:00 pm
content: Quote from: Kilrah on August 06, 2016, 04:35:50 pmAt least, that one does (amongst dozens) :https://www.conrad.de/de/logilink-powerbank-12000-mah-1040721.html---Let's make a quick calculation if you will :This 12000maH PB (powerbank) claims it can deliver 12Ah (ouch!)That means that it either includesONE12A LiPo orTWO6A LiPo (in parallel) ... I dont really think it could be more thanTWO(see the thickness).Then1Cfor each battery is either 12A (1 batt) or 6A (2 batt) but not less !---Therefore, the charging current (I saidCHARGING, notDISCHARGING) shouldNORMALLYbe either 6A or 12A to stay within the frame ofNORMALcharge cycle diagrams (that is a few hours charging, generally less than 6hrs depending on the battery technology and manufacturing quality).Then, if you are right (see your quote), that would mean that it takes that PBMORE THAN TWO DAYSto get charged ... no way!CONRAD.DEcould not possibly be so dumb to include such a poor device in their listed products !---Don't forget that even if a wall socket can deliver only 1A to the PB's micro USB charging connector, some internalswitch-mode circuitryis intended to increase this current !

author: NottheDan
author_rank: Frequent Contributor
timestamp: August 06, 2016, 05:51:23 pm
content: Looking at the linked pdfs they quote a charging current of 200-1600mA and a charging time of 15 hours at 1.5A.Though, looking at a 19600mAh powerbank of the same brand they only vie a charging time of12 hours at 1A. And the 20000mAh one gives10 hours at 2A.

author: ym58
author_rank: Regular Contributor
timestamp: August 06, 2016, 06:10:55 pm
content: Quote from: NottheDan on August 06, 2016, 05:51:23 pmThanks Dan, shame on me I did not even look at the specs in French(I only sticked to the second .PDF, less precise ...!).---So,'Max 15 Heures sous 5V 1.5A'is notTHATbad.But still, how come one can't find anycheap chipthat could deliver higher constant currents to charge LiPos (or Li-Ions) ... how can the mainstream market possibly accept such poor charging time performances ?---Any LiPo (or Li-Ion) can beTECHNICALLYcharged within a few hours with a proper CC (constant current) equaling its1Ccapacity.How can we, customers, accept specs stating15Hrsto charge a 5-ounce battery ?

author: Kilrah
author_rank: Unknown
timestamp: August 06, 2016, 06:35:24 pm
content: Quote from: ym58 on August 06, 2016, 05:35:00 pmNothingrequires youto charge a Li battery at 1C, it'sthe maximumyou can do on normal cells. The cell count in the powerbank is also irrelevant, it's the energy capacity that matters.About your Conrad powerbank:Pack "rating" (not always realistic, let's assume it is) is 12Ah @ 3.7V so 44.4Wh, so 8.8Ah equivalent @5V. They say "up to 15h", 8.8/15 =.... 0.6A.So this one also charges at the usual 600mA (losses ignored, it will probably actually draw about 7-800mA or so).The reasons for the low charge speed is a mix of convenience, cost, size and "no need for more".Having an USB charge port allows not supplying a proprietary charger (expensive, inconvenient to carry around for the user). But given that you have to assume the user might use any USB charger, including one that might not be rated for >500mA, and a charge controller that handles that actively is too much to ask from the cheap manufacturers.Then a 5-10W charge circuit would start to get pretty big compared to the power bank itself. Lastly, as we can see, that's how things are and nobody complains, most will actually rather want a cheaper powerbank than a more expensive one that charges faster... most people have them in their bag just in case "for emergencies", once back home it's not a problem to charge it all night. There are some that charge faster, but of course they cost more.Even I who have been using standalone Li-Pos for more than a decade and have universal chargers have never found the need to spend the 5 minutes needed to crack open my powerbanks to wire them to a fast charger, I just plug them to an usb charger laying around and forget them there for a while.

author: NottheDan
author_rank: Frequent Contributor
timestamp: August 06, 2016, 06:56:34 pm
content: Random thought: Having you looked into the balance chargers available to RC model enthusiasts?

author: ym58
author_rank: Regular Contributor
timestamp: August 06, 2016, 07:01:23 pm
content: Quote from: blueskull on August 06, 2016, 06:27:57 pmApparently, this one is QC2.0 certified, that's a big step forward compared to my cheesy stuff!!---Besides, reviews are not all good, is Xiaomi experiencing QC problems or is it just coincidental ?---BTW, your Chinglish's quite good, way better than my froglish!!!

author: ym58
author_rank: Regular Contributor
timestamp: August 06, 2016, 07:08:07 pm
content: Quote from: Kilrah on August 06, 2016, 06:35:24 pmYou're bloody damn right, but on the other hand nothing requires us to be happy with long-lasting situations ... otherwise there would be no chance for any progress !Personnaly, I always charge my batt packs at1C, be it with my lab P/S or my iMax B6 !

author: Kilrah
author_rank: Unknown
timestamp: August 06, 2016, 07:24:34 pm
content: Quote from: ym58 on August 06, 2016, 07:08:07 pmOf course not, but given the current situation if you wanted to do better $5 Chinese boards is not really the right place to look. Of course there are solutions to do better, but then you need to forget the condition I quoted in my first post becasue you're going to be making what amounts to a "premium product".

author: Siwastaja
author_rank: Super Contributor
timestamp: August 07, 2016, 08:24:40 pm
content: Quote from: Ranger14 on August 06, 2016, 02:20:19 am... Which is a prime example why you shouldn't base a design on a group vote by random people who have no freaking clue what they are talking about.18650 cells are most definitely used in parallel, which is their intended way of use, and has always been.

author: Siwastaja
author_rank: Super Contributor
timestamp: August 07, 2016, 08:40:22 pm
content: Quote from: ym58 on August 06, 2016, 07:08:07 pmCharging any random energy-optimized (as opposed to power-optimized) li-ion packs at 1C is very likely to cause severe lifetime issues on some, if not most cells.Most energy cells are rated at 1C absolute maximum charge rate, compromising the lifetime already, even with non-aged cells which still work optimally.On random, aged, salvaged cells I strongly suggest limiting yourself to about 0.5C maximum occasional charge rate, preferably less than 0.25C as your everyday charge rate, to maintain good cycle life.RC toy cells are optimized for high power discharge, and as a consequence, can tolerate higher charge rates too, so 1C is quite a normal everyday charge rate there, occasional peaks being somewhere around 3C. But this is not the case with consumer electronic cells which are optimized for higher energy density and lower price, not high power. There will be serious lithium plating, causing the cycle life to plummet. It can happen suddenly, a certain cell can work for 500 cycles just fine at, say, 0.6C, and be destroyed in less than 50 cycles at 0.8C. You can't know without destructive testing, so keep that charging slow enough.

author: ym58
author_rank: Regular Contributor
timestamp: August 08, 2016, 01:53:58 am
content: Quote from: Siwastaja on August 07, 2016, 08:24:40 pmI agree, and I suppose this remark should also work for LiPos.The best example being laptop battery packs that contain Li-Ions or LiPos which areALWAYSpaired in parallel.Quote from: Siwastaja on August 07, 2016, 08:40:22 pmThanks for the advice, that's good to know and take into consideration when it comes to pricey devices.---Concerning the prototype described in this thread don't forget that LiPos have been salvaged (from a Sony Vaio laptop battery pack) and that I don't really care about their durabilty ...My main concern is to reduce significantly the charging time that stretches over12-14Hrs at 0.6A(that is 0.3A per battery) !I would prefer to have them chargedin 3-4hrs(as most smartphones/laptops do) even if this means I will have to dispose off them after 50 cycles !

author: qnh
author_rank: Newbie
timestamp: August 08, 2016, 05:16:56 pm
content: Quote from: ym58 on August 08, 2016, 01:53:58 amI agree with you because Lithium batteries are getting cheaper and cheaper, and even free (as those you salvaged !).For me, it makes no sense to'maintain cycle life'(quote from @Siwastaja) at the expense of charging time ... it simply does not worth it : 12-14hr versus 3-4hr ... this range is just too wide !In Germany, we have recycling bins in nearly all shops, with treasures inside : Li-Ion, Li-Po etc ... recycling and using those batteries after testing and selecting them is definitely asustainableattitude ...

author: Siwastaja
author_rank: Super Contributor
timestamp: August 08, 2016, 07:53:19 pm
content: When charging at 0.25C, the charging time to almost full is four hours. At 0.5C, it's two hours. Talking about 12 hours is nonsense. We are talking about topping the final <1% in the CV phase, which is irrelevant. CV phase is never much more than one hour max in any practical case, and you don't need it at all if you don't want to do it.At low C rates, the cells are already very close to full when the CV phase begins. For example, at 0.5C, a typical laptop cell charged starting from 0% will reach approximately 90% charge after 0.9*2hours = 108 minutes, and topping off the last 10% would take maybe another hour. However, there is absolutely no reason to go to 100%, if you are happy with, say, 95%, which is quickly reached.So, when you seldom start from real 0% (but something like 10% instead), and don't need to get to 100% (95-97% being enough), C/2 charge is really very close to 2 hours.Note that the CV phase gets shorter when the charging current is lower, so it compensates for the longer CC phase!About maintaining cycle life: what I mean is that your salvaged cells abused at 1C chargemaybe dead after just 5 such cycles! It's not just worth doing, building the pack takes your time and physical resources. You are exceeding the design margins. Just go a bit lower. Even a tiny bit helps, there may be a huge difference between 1C and 0.9C. I recommend below 0.5C to have some margin. Only charge at the rate youreallyneed. If it must be fast, then sure. But note that you can't fully fast charge anyway, the CV phase will take longer accordingly when you increase the CC current.Note that "Battery University" is quite bullshittish. This graph, for example, shows li-ion cell being charged starting from 1V, which is utter bullcrap. As usual, they have no clue what they are teaching about.Many sources, including cell datasheets, also list CV phases that are way longer than actually needed in real life, giving the idea of very slow charging. The time required blows up exponentially when you are trying to squeeze the last 0.5%, but I never understood why you would want to do it. It's logical for the manufacturers to specify the capacity this way, however.

author: Kilrah
author_rank: Unknown
timestamp: August 08, 2016, 11:04:50 pm
content: Quote from: Siwastaja on August 08, 2016, 07:53:19 pmNot at all... we're talking about commercial powerbanks that house 4 or more 18650s i.e. 12Ah@3.3V or so, yet still charge them with only 600mA@5V out of a USB port... which is means charging with less than 1/10C and is what results in the whole thing taking those 12h or so.

author: ym58
author_rank: Regular Contributor
timestamp: August 09, 2016, 02:43:48 am
content: Quote from: Siwastaja on August 08, 2016, 07:53:19 pmNo one will argue on this ... you're right.But asKilrahjust explained in the previous post, we are not talking about an "ideal" single 16850 charge process but about a "strong" pack oftwo(or more, but in my case it's two)8.2Wh 3.7V LiPoswired in parallel !1C, in such a configuration, would theoretically be4.4A(for the two batt)... that means that charging them at 0.6A equals to charging them at0.15Cor so,hencethe unacceptable charging time ... andhencemy quest on this thread to get a better circuit thanFM9833Ewith its low 0.6A max charging current !Quote from: Siwastaja on August 08, 2016, 07:53:19 pm"Battery University"is not that crappy in the sense that it sums up in a readable and structured form all pertaining knowledge of the battery world including the latest technologies.Some credit should be given to them, at least on these grounds.That being said, you surely have noticed that there are numerous reader comments attached to nearly all the articles published in"Battery University"... which means that some constructive criticism is posted there, allowing readers (like me) to put the published articles into perspective !---Do you know of any other knowledgeable site about the battery world that you could recommend us to read ?---BTW, I have corrected theimproper 1-voltextrapolation that you came across in their graph, that will make it more acceptable I guess ...

author: Siwastaja
author_rank: Super Contributor
timestamp: August 09, 2016, 07:14:22 am
content: OK, I understood you guys wrong, because of how the OP stressed the need to charge at1C, at the same time talking about 12 hours. Indeed, charging at C/12 takes 12 hours by definition, and it's impractical because it's considerably longer than a night. To fix that, I recommend charging at C/2 if absolutely necessary, or preferably a bit less (C/3 or C/4).The problem with Battery University is the amount of misinformation and urban myths originated from there. The way the information is presented clearly does not help; quite the opposite, it leads the reader to enjoy reading and to believe it's a credible source. However, it appears to me that the quality has gone up considerably. Just some 5-10 years ago, it was total bullcrap to such a high level that it was a huge cringe to try to read through if you knew how the things are in reality. Still, most readers took their word because of the nice style of presentation, and most internet forum urban myths regarding li-ion originate from there, even though most of that stuff has already been removed or rewritten.Showing faked graphs with severe misinformation "just as examples to point something else out" is a huge problem, you should never ever do it, especially when trying to teach someone else! People will always refer to such graphs and interpret every piece of information they can get from those, because graphs are powerful format of conveying facts using data. This graph doesn't even state that the voltage information is nonsense, which would be the minimum requirement. Although, it would be easiest to simply use a graph with correct information - but that, of course, requires that you have the correct information, which is not true with "Battery University". I guess the author just simply thought that li-ion cells are discharged down to 1V. From the charging algorithm point of view, the starting voltage is an extremely important parameter - a cell starting at 1.0V doesn't go though that kind of charging graph at all.

author: ym58
author_rank: Regular Contributor
timestamp: August 09, 2016, 07:39:50 am
content: Quote from: Siwastaja on August 09, 2016, 07:14:22 amActually, there is a second graph just below that one on the same page, did you see it ?

author: Siwastaja
author_rank: Super Contributor
timestamp: August 09, 2016, 08:06:05 am
content: That graph looks less wrong and more realistic, although many  cells today perform better, i.e., reach much more than 60% at the end of CC even at 1C charge.That being said, even this graph shows the starting voltage clearly at or below 2.5-2.8V, which would most likely cause the real charging algorithm to go to the "conditioning" mode (or simply report "broken cell" and refuse charging), so even this graph is wrongish, although not catastrophically so.

author: qnh
author_rank: Newbie
timestamp: August 09, 2016, 04:15:35 pm
content: I think we are getting a bit off topic ... being obsessive on why we should NOT let any Lithium battery discharged under 3 Volts is sort of pointless as it makes sense to everyone here.I am also interested in finding a chip (preferably a"cheap chip"as ym58 quoted previously) capable of getting one or two Li-Ions/LiPos single cells charged in a decent time (few hours) and also able to provide a min of 2A output current.What would then be the best alternative to FM9833E ?

author: crazyguy
author_rank: Regular Contributor
timestamp: August 09, 2016, 04:55:00 pm
content: very cheap chipPower Bank SoChttp://www.injoinic.com/english.htmlIP5108Charger Current 2.5A, Boost Converter Output Current 2.1Ahttp://www.injoinic.com/doc/IP5108_brief.pdfhttp://www.gearbest.com/chargers/pp_421906.html?wid=21http://www.chongdiantou.com/thread-2357-1-1.html

author: ym58
author_rank: Regular Contributor
timestamp: August 09, 2016, 06:28:26 pm
content: Quote from: crazyguy on August 09, 2016, 04:55:00 pmThat's just unexpected ... there has been so muchblah-blahon this thread that I was close to give up finding credible alternatives to the FM9833E chip !Let me review those specs accurately and I'll surely have further questions to ask you then ...Thanks to you HKcrazyguyfor being so concrete after all this claptrapBe back soon.

author: qnh
author_rank: Newbie
timestamp: August 09, 2016, 06:45:23 pm
content: Quote from: crazyguy on August 09, 2016, 04:55:00 pm

author: Siwastaja
author_rank: Super Contributor
timestamp: August 10, 2016, 06:06:57 am
content: Quote from: ym58 on August 09, 2016, 06:28:26 pmI may have saved hundreds if not thousands of your hours by informing you of the problems related to your idea of always charging li-ion cells at 1C (partly based on my own, yet-to-be-published research), and by informing you that Battery University is not a good source for a beginner like you, whichyou, ignoring my expertise, started to blah blah against without better knowledge. I clearly should have seen at that point that you are not worth replying to.Designing something is more than just taking a random solution and applying it; understanding the relevant principles is paramount. I always try to stay relevant when talking about said principles, to save everyones time and avoid diverging to unnecessary nitpicking and blah blah.Everything in this thread has been concrete and important, and if you deny to see it, it's your problem and you'll just face it later.I didn't feel I need to diverge to charging voltage, but wanted to reply to the claimed premise that Battery University is "just fine" by showing all the severe errors that come up withevery graphposted originating from them. If they can't even get the basic voltage profile right, how can you trust them in other aspects, either?It would have also helped if you could write more clearly. When you keep blah blahing about charging at 1C, and reason it so that you don't have to wait for 12 hours, I logically conclude that you have have been misinformed (by sites like Battery University, for example) that charging at less than 1C takes 12 hours. This kind of misconception is not uncommon; not all people understand C rates at all, and that's all OK, as long as you are willing to learn.But now I know I don't need to invest any more of my time in you. Thank you and good bye.

author: Skimask
author_rank: Super Contributor
timestamp: August 10, 2016, 06:49:48 am
content: ^^^^This(or is it "That"?)With that being said, I've been using those cheap ebay PCBs that come with the TP4056 & DW01 along with a bunch (bunch = 12) of relatively equally used 18650's (same brand, same 'color', look to be roughly the same age, etc) for a few months now, with the pack feeding a TPS63001 prototype PCB upconverting to 5V @ ~1A, connected to a 4pk of USB-A plugs. Takes forever to charge the whole thing if it's dead-dead, but lasts forever (maybe slightly less) on a charge. 12x ~2200mah 18650's = a bit less than 100WH...for the cost of some junkPictures to follow...(Don't expect too much. It's thrown together with duct-tape, bailing wire, and clothespins. Someday I'll find that fire-proof for the thing...just in case)

author: ym58
author_rank: Regular Contributor
timestamp: August 10, 2016, 07:51:30 am
content: Quote from: crazyguy on August 09, 2016, 04:55:00 pmHello Crazyguy,A few questions :Thanks !

author: ym58
author_rank: Regular Contributor
timestamp: August 10, 2016, 07:59:27 am
content: Quote from: Skimask on August 10, 2016, 06:49:48 amQuote from: Skimask on August 10, 2016, 06:49:48 amWe're in the same boat together, buddy ... trying to make practical things from scrap/junk without spending a dimeAwaiting your pics.

author: crazyguy
author_rank: Regular Contributor
timestamp: August 10, 2016, 08:11:28 am
content: Quote from: ym58 on August 10, 2016, 07:51:30 am(1) The IP5108 brief datasheet said VREG (pin 12) is 3.1V LDO Regulator Output, 50mA (max)I think it means the L4 (pin 13) is connected to the VREG (pin 12)IP5108 datasheethttp://www.injoinic.com/doc/IP5108_brief.pdf(2) the tablegreen color -> IC Part Number, IP5101 ....yellow color -> discharge current (A)pink color -> charge current (A)(3) according to the package, I would guess it is a IP5108 chiphttps://item.taobao.com/item.htm?id=534722661076&ns=1&abbucket=5#detail

author: ym58
author_rank: Regular Contributor
timestamp: August 10, 2016, 09:43:10 am
content: Quote from: crazyguy on August 10, 2016, 08:11:28 amI am not quite sure I understand howVREGworks.What that3.1V LDO Outputis supposed to control ?And why shouldTWOoutputs (VREGandL4) be connected together ?Quote from: crazyguy on August 10, 2016, 08:11:28 amJust to make sure I got it all clear :Charge= constant current (CC) delivered by the chip to the batteries during the charge cycleDischarge= current that the chip is able to output to the load (smartphone, iPhone ...) via the two5V/VOUTpins (5-6)Is that correct ?

author: ym58
author_rank: Regular Contributor
timestamp: August 10, 2016, 09:56:46 am
content: Quote from: blueskull on August 10, 2016, 09:50:28 am

author: crazyguy
author_rank: Regular Contributor
timestamp: August 10, 2016, 10:00:54 am
content: Quote from: ym58 on August 10, 2016, 09:56:46 amyes, you are right, 3, 4 and 5 LED configuration used for battery level indication.

author: crazyguy
author_rank: Regular Contributor
timestamp: August 10, 2016, 10:14:39 am
content: Quote from: ym58 on August 10, 2016, 09:43:10 amIP5108 is a 2 in 1 power bank solution (charger + booster)correct, Charge means (battery charger current), Discharge means (boost converter output current)

author: ym58
author_rank: Regular Contributor
timestamp: August 10, 2016, 10:56:24 am
content: Quote from: crazyguy on August 10, 2016, 08:11:28 amI am very interested in theIP5109, but don't feel like making my own PCB around this chipDo you know of any powerbank that would use this chip (as the Miller ML-106 with the IP5108) ?

author: crazyguy
author_rank: Regular Contributor
timestamp: August 10, 2016, 02:17:53 pm
content: Quote from: ym58 on August 10, 2016, 10:56:24 amIP5109 chip in operation is very hot, > 115CIP5109 demo board reviewhttp://www.chongdiantou.com/thread-1731-1-1.htmlno idea which powerbank use this chipMiller taobao shophttps://miller162.taobao.com/ML-106 V1.0 (IP5206)https://item.taobao.com/item.htm?id=534400802077Charger ML-102 V9.0 2015use IP5206http://lygte-info.dk/review/Review%20Charger%20ML-102%20V9.0%202015%20UK.htmlML-102 V9.0 Power Bank (Russian)http://mysku.ru/blog/china-stores/35821.htmlIP5108 and IP5206 are pin-to-pin compatible

author: ym58
author_rank: Regular Contributor
timestamp: August 10, 2016, 05:09:02 pm
content: Quote from: crazyguy on August 10, 2016, 02:17:53 pm---I'd like to test thisIP5109board and use chunks of this :here :and there :What do you think ?Where can I purchase one ?

author: crazyguy
author_rank: Regular Contributor
timestamp: August 11, 2016, 03:50:57 am
content: use a large heat sink will increase the size of the powerbankI don't think you can purchase this demo board anywhere, send a email to the IC company maybe they would be kind enough to give you a copy for testing

author: ym58
author_rank: Regular Contributor
timestamp: August 11, 2016, 04:51:52 am
content: Quote from: crazyguy on August 11, 2016, 03:50:57 amWell it's not so large, the width is only14mm(0.55 inch) and the height6mm(0.23 inch) !And I was thinking I could trim its length according to the hot surfaces it has to be glued on on each side of the PCB ...Quote from: crazyguy on August 11, 2016, 03:50:57 amThat's what I'll do.IsChangdiantoua distributor only or the original IC company ?Apparently, their website is about video rentals ... ?!?

author: crazyguy
author_rank: Regular Contributor
timestamp: August 11, 2016, 06:55:08 am
content: Quote from: ym58 on August 11, 2016, 04:51:52 amchongdiantou is a forum interested in charger, they are not distributorthe IC company name is INJOINIC Technologyhttp://www.injoinic.com/their website saysFor English Datasheets, please mail to SERVICE@INJOINIC.COM

author: crazyguy
author_rank: Regular Contributor
timestamp: August 11, 2016, 07:11:59 am
content: Quote from: blueskull on August 11, 2016, 06:14:49 amBQ24195 can boost to 5.1V@2.1AI2C Controlled 2.5A/4.5A Single Cell Charger with 5.1V 1.3A/2.1A Synchronous Boost Operationhttp://www.ti.com/product/bq24195

author: ym58
author_rank: Regular Contributor
timestamp: August 11, 2016, 10:03:56 am
content: Quote from: blueskull on August 11, 2016, 06:14:49 amQuote from: crazyguy on August 11, 2016, 07:11:59 amThose ones (BQ24195andBQ24295) are killers and do everything I want (Boost 5V/1.5A or 2.1A and up to 4.5A CC charger) but honestly it does not worth designing a new PCB just for the beauty of gestureIn addition, I have no knowledge in I2C management designing ...I would be better off with a ready made solution like theIP5109stuff ....

author: ym58
author_rank: Regular Contributor
timestamp: August 11, 2016, 10:05:02 am
content: Quote from: crazyguy on August 11, 2016, 06:55:08 amThanks, I've just contacted them ... will let you all know about the status here.

author: ym58
author_rank: Regular Contributor
timestamp: August 11, 2016, 01:55:28 pm
content: Quote from: crazyguy on August 11, 2016, 06:55:08 am

author: injoinic
author_rank: Newbie
timestamp: August 12, 2016, 03:17:48 am
content: Quote from: ym58 on August 11, 2016, 01:55:28 pmattachments is the datasheet of IP5318. IP5318 is a QC3.0 soc that has passed qualcomm QC3.0 verificationbut how to upload attachment bigger than 1MB

author: ym58
author_rank: Regular Contributor
timestamp: August 12, 2016, 05:05:36 am
content: Quote from: injoinic on August 12, 2016, 03:17:48 amHello Injoinic,Thanks for joining the EEV community and posting in this thread ("DIY cheap powerbank (technical suggestions R welcome !") which I am the OP.I suggest that youCOMPRESSthe size of your attachments, thus allowing you to post them here.Another suggestion is to host the .PDFs somewhere in the cloud (for example inDROPBOXorGOOGLE DRIVE) and give us apublic share linkhere !Could you also provide us with theIP5109andIP5209datasheets ?

author: injoinic
author_rank: Newbie
timestamp: August 12, 2016, 06:25:27 am
content: Quote from: ym58 on August 12, 2016, 05:05:36 amthanksplease download IP5209 and IP5318 datasheets @http://www.injoinic.com/doc/pdf/IP5209%20datasheet%20v1.0_en.pdfhttp://www.injoinic.com/doc/pdf/IP5318%20datasheet_en%20V1.0.pdfFor Your Information:IP5109 has been upgated to IP5209 with pin to pin match.IP5209's efficiency is higher than IP5109 @charger and booster.And IP5209 has more featue such as DCP and BC1.2 support.but his price hasn't changed.

author: ym58
author_rank: Regular Contributor
timestamp: August 12, 2016, 07:04:05 am
content: Quote from: injoinic on August 12, 2016, 06:25:27 amThanks for your links !Two questions :#1 have you already designed anIP5209-based prototype board like this one (Lithium charger and 5V booster) ?#2 if yes, how is it possible to get samples for further testings ?

author: injoinic
author_rank: Newbie
timestamp: August 12, 2016, 07:17:51 am
content: Quote from: ym58 on August 12, 2016, 07:04:05 amplease give me your mailing address.and you can also buy a powerbank using IP5209 IC from amazonsuch as:https://www.amazon.com/ROMOSS-20000mAh-Portable-External-Recharger/dp/B01DM4EYO8/ref=sr_1_15?ie=UTF8&qid=1470986008&sr=8-15&keywords=romoss+powerbankhttps://www.amazon.com/20000mAh-Flashlight-Portable-External-Battery/dp/B01AAUFTN2/ref=sr_1_2?ie=UTF8&qid=1470985337&sr=8-2&keywords=arun+powerbankhttps://www.amazon.com/mobile-power-ARUN-Universal/dp/B01D4F07X2/ref=sr_1_8?ie=UTF8&qid=1470986225&sr=8-8&keywords=arun+powerbanketc...

author: ym58
author_rank: Regular Contributor
timestamp: August 12, 2016, 07:42:30 am
content: Quote from: injoinic on August 12, 2016, 07:17:51 amI will send you my mailing address byPMright away.Thanks for the links, however I am rather looking for OEM parts.BTW, are these three PowerBanks (ARUN and ROMOSS) allIP5209-based ?

author: injoinic
author_rank: Newbie
timestamp: August 12, 2016, 08:10:16 am
content: I will send you my mailing address byPMright away.----- your mailing address is at france?our assistant is finding Which Courier can reachBTW, are these three PowerBanks (ARUN and ROMOSS) allIP5209-based ?---yes

author: andry
author_rank: Newbie
timestamp: August 12, 2018, 07:57:27 am
content: Hi @injoinic,I'm very interested in your chip IP5209. Could you share the documentation on how to access I2C registers? Been searching it online, have not find any.Thanks.

author: uktron
author_rank: Newbie
timestamp: January 29, 2019, 01:49:41 pm
content: IP5306 registers map:https://yadi.sk/i/dRp0HTF4oPCo2gIP5209 IP5109 IP5207 IP5108 registers map:https://yadi.sk/i/oNhqTei36jFwSgA bit more about IP5108, but only russian language (google translater helps you):https://wiki.iarduino.ru/page/Battery_Shield/Battery Shield Libary for arduino (with Register description):http://iarduino.ru/file/344.html

author: andry
author_rank: Newbie
timestamp: January 30, 2019, 07:38:32 pm
content: Wow... big thanks!