Tp4056 and 18650 build

​I'm planing to build a battery pack this summer and i was wondering if this setup could work. The tp4056 boards are really cheap and I've got a few lipos around I want to make a use of it. My goal is 3s2p or 4s2p with one board per lipo cell (even  7p is of interest, but that is another build). Now I was thinking wiring from Vout on the board to a motherboard connector (something with a lot of connectors)  so that I can disconnect the entire bank for charging. Take a look at the picture, it is supposed to be a 3s pack, but I'm not sure if it will work. When charging =NO load and when load = no charging. Tp4056 have a built in protection circuit why I would like to use those. I would appreciate your help on this. What I know about the board is that Batt+ and Vout+ are same, but Batt- and Vout- are separated by a mossfet that protects the battery. And of course 3s lipos batteries do not sum up to 12V exactly, that is not the issue here. Question is if this setup would work, i.e. When charged, I can connect them in series and the output is ~12V or I fry the circuit/batteries/both!?

Topic by GoranM6 3 years ago


iMAX B6 Digital Battery Balance Charger

Hey i just found this cheap charger on eBay and i was wondering if it would be able to charge a pack of 18650(unprotected) 3P4S safely? i figure i could just run the charger to each 3P set and be confident it want gas/explode? http://www.ebay.com.au/itm/iMAX-B6-Digital-Battery-Balance-Charger-and-Discharger-For-Lion-LiPo-LiFe-GL-/282048500472?hash=item41ab6692f8:g:ACQAAOSwH6lXRSCK

Topic by andrewlapham2010 2 years ago


18650 at 0V and open-circuit? Answered

Something odd happened today. I went to use my Skyray king flashlight, but the output was very dim. I pulled the batteries out, 3 were at 2.7V, and one of them was completely dead. IDK how they discharged as I charged them not too long ago. They have protection PCBs in them so that is the first thing I suspected that tripped in the dead one. Sticking that one on the charger did not reset the protection PCB. So I pulled the insulation of the dead battery, However it is the battery itself has failed high impedance / open circuit. Even bypassing the protection PCB, I still only measure 0.001ish volt measured across it (the real measurement varies a large amount) and only uA of current short circuit. I applied 4-40V to it and measured no current flowing into the cell. Certainly open-circuit. I just thought this was peculiar, what is going on with this cell? I figured if it discharges all the way the internal resistance will go up a little, but to the point of becoming a complete open circuit!!! It is possible that a internal bond broke?

Question by -max- 3 years ago  |  last reply 3 years ago


18650 battery pack question

Hello everybody, I need to install (build) a recharging battery pack for my plant shelf.  it will be running an arduino nano, just 3 leds (3mm 20ma each) 1xNTC and 1x water sensor probes (nails).--  no LDR no yellow LED. . I was thinking about getting a 2x 18650 battery holder - I need more battery hours, should we wire the batteries in parallel to get more mAh and boost them 3.7V to 5V. so basically this is what I am trying to custom build to get more hours; DIY Mobile Power Bank Case Kit . I would just buy the mentioned product BUT under specifications>battery it says the capacity range: 1000mAh and below. but the batteries I have are 3.7V @ 5000mAh. does this mean that the remaining 4000 will be lost because the system can't handle it?  . basically what I am asking for is how can I make a long lasting arduino nano powering 18650 battery pack BUT also with a recharging module. these are the items I found that may work together, please remember that I have no electrical experience from before. I have learned everything that I know from instructables, this is a too advanced build for me to figure out without asking a few questions. thank you for your patience, let me know if I have to clear anything out. batt holder:  recharger: boost: am I even in the right track with this thing? can these be connected together and a switch. again, the goal is max battery life.. maybe add 4x 18650 - 2in parallel + 2in series, 7.4V to arduino Vin, eliminate the booster, even more battery life ? . thank you in advance, love & peace akin,

Question by Akin Yildiz 4 years ago  |  last reply 4 years ago


18650 protection board limitations

Hi ThereI've been lucky enough to stumble across a large quantity of brand new 2600 - 3300mAh 18650 cells and I'm wanting to find some DYI projects to put them to good use. 200W flash light, electric Go Kart or a basic power wall comes to mind. However first things first Ill be needing to build them into a packs and connect them to protection modules but Ive got a few questions:Protection modules come in so many flavors. 2S - 3S - 4S - 5S - 5S5P and bigger.. Do you choose the module based on how many cells you have in total and then just use a DC-DC converter to get the required voltage? Or do you try to get as close as possible to the voltage needed in series first and then find a module that suits? What is the most versatile configuration?Can I connect 5S5P pack to a 5S module? Can I keep increasing in parallel with no consequences? Like for example can I connect a 5S15P pack to a 5S model and expect the module to be able to balance and charge the pack back up? I understand there are Amp draw limits to watch out for too. The module I was looking at is below.https://www.ebay.com/itm/191978019369Also this module requires a charge voltage of 21 volts at no more than 5Amps. Where would I be able to find a charger like that? A laptop power brick maybe?Any guidance would be great as I'm keen to learn as much as possible!Thanks in advanced!

Question by Plangy 9 months ago


How do I recharge my 18650 batteries

Hello everyone, and good day! I am attempting to add recycled laptop batteries to an old radio of mine, making it portable. I Need 12v to run it. I have made a battery pack already, but am worried that if I just use a 12v power supply to charge them, I might ruin the batteries. also, I want to be able to plug in and listen while the batteries charge. Is it true that all I need to do is to make the input and output at the same point? I hope this makes sense. Thanks in advance!

Topic by jason.eck 2 years ago  |  last reply 2 years ago


having a little trouble picking out 18650 batteries for my 3A flashlight? [answered]

I am looking for a few batteries for my flashlight. i have one the LC 18650 but it will only lash a few days of use. OK, i do want a high quality 3A battery (for 1000 LM from my light) so one that that supports the current. i prefer one with a safety circuit in it, one that holds at least 2200 MAh, ok, i shop for that, but what is the difference between: LIR  18650, LC   18650 (the one i have) (i think LC stands for "low current drain"), GTL 18650, TR   18650, AW   18650, (i know this offers 5A, but its expensive and rare.) BRC 18650, XSL  18650, TRC 18650, i know the AW battery offers 5A max.

Question by -max- 7 years ago  |  last reply 7 years ago


18650 Battery Question - Battery Powered Heaters

Hi, I have a question before I begin a project.  I have carbon heater fabric that I want to make heated grips for my snowblower with.  I want to connect the ~0.5 meter x 15mm carbon tape to 2x18650 cells. Are there any precautions I need to take to make sure I dont "short" the batteries and cause damage/explosion etc?  I know technically I am shorting the batteries and making heat.. but how do I know if it is damaging the batteries or putting myself at risk for explosion?  

Topic by DanaF5 3 years ago  |  last reply 3 years ago


Can I charge and use 18650's simultaneously or better charged first, block from solar, then use with the power inverter?

Hi all, I have been into DIY Solar / Wind for a while. Everything been working great until I planned to replace my lead acid batteries for the 3.6V LG HG2 3000mAh 18650's. With the lead acid I could power my house anytime during day (using solar panels) or night off-grid with ease. So, I bought a lot of 200 18650's and spot welded them in 4S50P. Balanced them, and all that good stuff (time consuming, and a learning experience). Installed a BMS on it too, have a 30 Amp charge controller for 4x100W solar panels which I reserved for this project. Now, I have been searching for a while if these 18650's can be used anytime (connected to solar panels and with the power inverter feeding the house at the same time) ... with no success.

Question by LuisE47 1 year ago  |  last reply 1 year ago


lithium 18650 series first or parallel?

Hey all Looking at doing a lithium battery build but trying to cut down on soldering or spot welding. My idea is to use a stack of 3 18650 batteries in series pushed inside a piece of PVC pipe, thus making a 12V tube and then having multiples joined together to make the final battery Is there any reason why people mostly use a set of batteries is paralel then series?

Question by pickstock 1 year ago  |  last reply 1 year ago


why are my 18650 cells shorting? Answered

After realizing lead acid batteries are sooo 1859, I decided to construct a battery pack out of 18650 cells. I soldered 4 in series on the top half of the cells. When I went to do the bottom half I found that touching the wire from one negative terminal of one cell to the positive of another cell it short circuited. At first I thought I had a bad cell so I checked all of them and they were all fine. I desoldered them and tried putting only 2 in series, same thing. The cells still put out ~3.7 so I don't see the problem. please help. 

Question by fossilshark 3 years ago  |  last reply 3 years ago


How to make 18650 circuit protection?

Help me to build circuit protection for single cell without IC. I need schematic too. Thank you.

Topic by myhobbies 5 years ago


18650 iPod Touch 7805 Charger Answered

If I had 2 18650 batteries (3.7V each in series = 7.4V) could I use a 7805 and a female usb connector to make a cheap iPod charger (iPod Touch)? I know that the 7805 will provide 5V @ 1A but is it efficient enough to charge the battery up a good amount? The last one I made I used a 9V battery (big mistake) but it just drained the ipod battery :( My question is do 18650 batteries provide enough current to charge an iPod Touch?

Question by Mdob 8 years ago  |  last reply 6 years ago


Where can I find good 18650 cells?

I want to build a custom Li-Ion pack using the 18650 cells. But, when I go to look some up online, all that really turns up are the knockoff brands in which they claim a stupidly crazy high mAh rating. So.... where can I get some good cells?

Topic by Dashing Rainbow Dash 2 years ago  |  last reply 2 years ago


How to build battery pack 9.6v from 18650 batteries?

I would like to create a good battery pack for my dead hilti drill. Originel nc-cd 9.6v battery. I have some panasonic cgr18650cg batterys here.  But when 3 in series, the voltage is higher. Maybe the drill can work with a higher voltage but I dont know. Will it work, would like to create first a 3S pack and maybe later a 3S2P  I need a PCB and thinking something like this one : http://www.ebay.nl/itm/12-6V-8A-w-Balance-Li-ion-Lithium-18650-Battery-BMS-PCB-Charger-Protection-Board-/321853922824?hash=item4aeffd1e08 Or this one? http://www.ebay.nl/itm/3-Cells-Li-ion-Battery-18650-14450-Input-Ouput-Protection-Board-PCB-12-6V-8A-/321804037521?hash=item4aed03ed91 And how to charge a pack, can I use a common 12v laptop adapter or other adapters or specia li-ion charger? I dont think the original ni-cd charger can be used with pcb's above?

Question by rnijland 3 years ago  |  last reply 3 years ago


how much backup can be obtained from 18650 (2600mah) battery and 5w led bulb as a load?

Hello; i have some basic questions and want to clear my mind. i want to create a portable power bank using 2*18650 (2600mah) rechargeable battery and 5w usb plugged led bulb (5v). So keeping in mind the above values how can i determine the maximum backup this setup can provide? i would highly appreciate if you provide some real life examples to calculate the above mentioned values.

Question by askfriends 3 years ago  |  last reply 3 years ago


Question: I made a power pack of 18650s with protection board. Is voltage drop normal?

I made a power pack using 18650 batteries from an old laptop. All batteries tested individually are good. 4 batteries in 2S format. I used a cheap 2S 3Amp rated protection board I got on Ebay from China. I correctly connected all the terminals and properly soldered, B+/B- to the +/- of the final ends of battery and BM to the middle.The voltage measured directly at the battery terminals (at B+/B-) is 8.4 volts but at P+/P- (the input/output terminals of the board) it measures 7.5. Which means this board will not produce more than 7.5 volt usable voltage even when the batteries are fully charged to 8.4. Is that expected and normal? or is there a problem with the board.Thanks for help.

Question by ju1234 5 days ago  |  last reply 4 days ago


Batteries

Hi, I'm building a mini BB-8 unit for a project and going to make many more for a club. My biggest problem I'm encountering now is the battery needed to power it. The entire circuit draws around 500mAh and runs  on 3-5V. I don't think a 9V battery is enough to power it or even a AA battery no matter how many i put on it. The online guides that I found uses 18650 batteries either salvaged or bought. However, from where I come its very expensive to buy this batteries and it the charger cost even more. So I was thinking of buying this cheap 2400mAh powerbank that is sold commonly here. It outputs 5 volts and can be charged by USB. This powerbank cost about the same price of a 9V battery but only have life span of about 2 months which is good enough in my opinion. My main question is are there any other alternatives to power this circuit at a cheap price and is it possible to use a powerbank to power this circuit? Tq for any help and suggestions.

Topic by KhayhenS 3 years ago


Big battery bank project. Circuit related questions?

Hello everyone! I have a project in my mind and I would love some guidance and some ideas if possible. I already have a lot of 18650 batteries in an “acceptable” state (1800-2100mAh each) and I am planning to make a large battery bank, for use in camping mostly (smartphone charging, led bulbs, electrical air pumps 12v, etc) I did read a lot of articles in here about battery banks, but i didn't find something as complex as my idea. I have already made a 12v battery pack with 12x18650, 3 rows in parallel, of 4 in series in each row. My goal was to operate a 12v air pump for inflatable mattresses. It worked like a charm! (Also created with instructions from here! Thanks for that!) But since my “DIY disease” does not leave me in piece… I want to build a large enough pack that can support the following: 1) 12v car plug 2) 5v/1A + 5v/2.1A USB plugs 3) charge circuit for the battery pack, so I will no longer have to remove the batteries to charge them separately 4) switches in each plug 5) led voltmeter also with switch ?) at some point I would like to add a circuit to charge it with a solar charger or a mini wind turbine that i will create at some point with my 3D printer, but for now let stay with the basic stuff! For the case i will use a modified screw organizer case, with those classic 18650 black holders from ebay. (photo below) The case will fit almost 8 to 10 holders (4x18650), so we are talking for 32 to 40 batteries... My main concern is the circuit design. I have done a few simple things in the past, but this is a bit more complicated and that is why I want your guidance/ideas. How to safely connect all those things together or maybe suggest a different plan/design, cable thickness, etc... Links gathered so far: I am thinking about 4S in a row. Is that too much? Or should i consider 3S? 3S Li-ion Charger PCB with BMS For charger... something like this maybe? 12.6V 5A Charger optional... maybe i could fit sothing like that, for laptop charging? 150W DC-DC Boost Converter for 5v 1/2.1Amp charger i m looking at this. 5A Charger Step down Module for usb/12v plugs/voltmeter i am considering this option. Thanks in advance for your time!

Question by the_phantom_boy 2 years ago  |  last reply 2 years ago


How to reduce amperage from an 18650 li-ion cell to 3 amp 1.2 Volts?

Project is to adapt an 18650 cell to power an RC Glow plug. I just need to get the battery to power the glow plug to a working safe level. From my multi meter I read around 5 Amps out of the battery and around 4.3 Volts when fully charged. I have already tried a 2.7 and 3.3 Ohm resistor and its not worked. These look to have reduced the Amperage far to low. By plugging the battery directly to the glow plug it burns the plug out. From my understanding I need to reduce the supply down to 3 Amps and 1.2 Volts. Anybody have a suggestions? Further reading on the glow plug: http://en.wikipedia.org/wiki/Glow_plug_(model_engine)

Question by Harb247 6 years ago  |  last reply 6 years ago


how to make 12v battery from 18650 li ion batteries?

Hi, I have this led strip  http://www.supernight.cc/supernight-tm-5m-16-4ft-smd5050-rgb-double-row-600-leds-tube-waterproof-led-flexible-strip-light-12v-120led-m-strip.html Working Voltage is 12VDC. Working Current/meter: 0.8-1A the strip is 5 meter. 18650 x4 = 14.4 v 18650 x3 =10.8 v How can I make it work with 18650 li ion batteries? And how many battery must I use and how can I do that? I think that I need driver or booster to get a stabil 12v! work-time I need 5 h

Question by Cr77777 2 years ago  |  last reply 2 years ago


About boosting battery volts? Answered

 If i use an XL6009 module to boost up my battery for example from 3.7 to 5 volts how it will effect on the battery my battery will drine much faster ?  will stay the same ? 

Question by NivA2 2 years ago  |  last reply 2 years ago


Need help designing 18650 battery pack.

Hey guys, I'm trying to transform my JBL iPod deck which uses 13v 2.5Amps into a wireless bluetooth speaker for a better use. I have a couple of 18650s which has a capacity of 2500mah so i tried to connect 6 batteries in series and got 12.8volts but the issue is the battery capacity doesn't increases. Also some of the battery are 2.3v and 2.89v when fully discharged and has voltage of 3.6v as usual. So my doubt is can i connect 3x2.3v + 2x2.89v battery in series and 3x2.3v and 2x2.89v battery in parallel with the series ones to make it achieve more battery capacity?? If not how do i make a battery pack for 12v with better performance. The battery i have is Panasonic CGR18650C.

Question by ansaridanish 7 months ago  |  last reply 7 months ago


Need help re-proposing 18650 cells into a E-bike battery Answered

So I was lucky enough to snag 35+ Temperature recorders from work today, Each with a 18650  cell (or two) inside. I've already made sure there wasn't a Deposit or return credit on them first so no problem there :) And I already know how to test each cell to see if they hold a charge. Does anyone have some suggestions about how to wire them all together? I was looking at This Movie Earlier and seems they used 30X 18650 cells to build a 37V battery pack My biggest concern is balancing the cells. since 3 are wired in parallel (then 10 groups in series) it seems to me that each cell may receive a slightly different charge. I'm trying to find a 9-cell balancing charger but no luck quite yet. Even if I do, does anyone think that will cause an imbalance in each of the three cells wired in parallel? Also each cell has some sort of an over discharge regulator on it as well. I'm wondering if they would be a factor in charging/Discharging the cells. (First time I've used this many 18650's in one project in a parallel/series circuit ) Any thoughts would be appreciated; I'll be sure to give a Best Answer ;) Hope to hear back soon! Wired_Mist

Question by Wired_Mist 2 years ago  |  last reply 2 years ago


How can I make a 3.3v Solar power supply that uses an 18650 battery?

I have a project which I would like to make self sustaining solar powered that runs 24hrs a day. the electronics themselves use between 60ma and 220ma of power. the 220ma is for about 1 second every 2 minutes when the device transmits it's sensor's data, the rest of the time it is 60ma to 80ma. I want to make sure that the circuit has overcharge and over discharge protection for the battery as well as voltage regulation to between 3v and 3.3v for the load. I have been searching and I cannot seem to find a premade solar controller board that will do what I need. If there is one <$20 USD please point me in that direction, but I would still like to learn how to build one.

Question by funinalaska 3 years ago  |  last reply 3 years ago


How to make a lithium-ion, usb power supply?

Sorry, but i have 4 18650's, and want to make them power a usb port. how do i need to set this up?

Question by theboygenius 5 years ago  |  last reply 5 years ago


Lithium Ion protection circuitry?

I was wondering.... The protection circuit for li ion cells in phones; is it a sort of regulator for the battery when charging? Or does it just stop the cell from being drained too far? I was wondering if I could use the circuitry from the prismatic li ions found in mobile phones for a 18650 battery....will the difference in capacity be a problem?

Question by .Unknown. 8 years ago  |  last reply 7 years ago


Am I missing something or is this battery charger just insane?

I bought this cheap charger that charges 2 Li-ion 18650 on eBay: https://www.ebay.com/itm/182586752606?ssPageName=S...But it charges them in PARALLEL!So if I put charge two batteries that have a different voltage, the charger will drain one and charge the other one at a pretty high current.If one battery is older, or has a different chemistry, it must not healthy to charge both.If I decide to charge only one, will it push too much current into it?If someone accidentally inserts one in reverse...If you want to charge 2 batteries that are exactly the same, make the charger a built-in feature in the device that uses the batteries, why disconnect them. Used batteries will always have a different voltage!I used to charge them with this cheaper charger, but I recently found out it charges them to 4.30V sometimes, and I want to be able to charge more than one at once...I don't care about charge time since I have a bunch of batteries always ready to use, prefer not to have our house burn down, but don't want to spend too much $ on a charger. Watt do you think of these? I don't want to pay 8x the price to have a charger tell me the voltage and be limited by USB cable's current...https://www.ebay.com/itm/VONTAR-LCD-Intelligent-Ba... ("smartest" & most expensive. Still, only tells the voltage)https://www.ebay.com/itm/Liitokala-Lii-202-18650-2... (confusing)https://www.ebay.com/itm/4-Slot-Smart-Battery-Char... (not "smart" but seems the best IMO)https://www.ebay.com/itm/50-1000MA-Lithium-li-ion-... (Hmmm...)Because we all know what can happen with an 18650 gets angry... Though I have used this charger to charge 15 y/o 19650s that were 0V, back to normal and they are like new now...

Topic by Yonatan24 9 months ago  |  last reply 9 months ago


Operate a 12v/6Amps air pump, with DIY battery pack? Answered

Hello guys... I have an electric air pump and i want to operate it with a battery pack (for camping purposes, away from any kind of electricity source). Its a 12V/72W pump (works with car lighter connector) so by my poor calculations, i need something that can give me 6Amps for at least 5-10 minutes. I have a lot of 18650 batteries in my disposal, so i thought that i maybe can put together a portable battery pack, so when i go camping for example i can carry it with me. My circuits design skills are... nonexistent... My DIY skills are reasonable... so my questions are: 1) Is it possible to create something that can provide at least 5-10 minutes operation, once per every charge? 2) If yes... can you please tell me or point me at the right direction so i can accurately calculate the amount of batteries that i need and the proper way to connect them? 3) or... any other easier "portable" solution? for example something lighter and cheaper than a motorcycle battery...? Thank you for your time! :)

Question by the_phantom_boy 2 years ago  |  last reply 8 months ago


How to charge a Powerpack of 18650 li-ion cells 4s3p 14.8V?

I plan to make a portable audio system with 4 speakers and a subwoofer which are driven by a 12v TDA2030A 2.1 Amplifier. Everything is already packed in a small enclosure (approx. 30x15x30cm) and works fine so far. At the moment the amp gets it's signal from a 3.5mm audio jack and the power is provided via a 12v 1.5Ah wall wart. That's what I have for now. But that's not really portable right? So to complete my project I want to add 2 more things - a bluetooth receiver powered with 5v and of course I need to get this thing of the mains. That's where my questions actually starts. I've read tons of forum posts, instructions and watched a lot of videos about making a 12v battery pack but I'm confused with all that information. From what I've read 18650 Lithium-Ion batteries have an excellent power density and would suit my system best (small enclosure and portable). But of course I'm open for new ideas anytime. I planed to make the power pack out of 4s3p 18650's from an old laptop battery (don't have the exact data of them yet). So the pack would provide about 8Ah at 14.8V nominal. With a step down converter to 12v it't could power the amp and for the bluetooth I would use a car usb adapter to get the 5v needed. So far so good, but regarding the power pack I have a few questions. 1. Would a 3s4p (11.1V) arrangement be good enough to power the 12v amp since the 11.1V are in average right? 2. The biggest question I have is - How to charge that thing? As I want to have it as portable as possible, to be able to charge it anywhere from a normal power socket would be ideal. I know there are dedicated chargers for lithium batteries but they are quite expansive and not really handy to carry around. Is there any other solution to handle that? 3. BMS, PCB - I'm confused. From what I've read, to charge multiple cells they have to be in balance right? An over-charging and over-discharging can lead to fire/explosions and to prevent that a BMS is essential right? But first - how do i connect that BMS? Only to each of the parallel strings or to every single cell? Second, is it possible to use that BMS to charge the pack? Maybe also in balance? 4. For the case that the 18650 from the laptop battery are undercharged, where is limit to withdraw them and to charge them to balance with a TP4065 at 1A? That's it for now. Sorry for the long text and thank you for reading through it. I read so much on the net but didn't find the right answer for me.

Question by Johnny-Pi 2 years ago  |  last reply 2 years ago


Wanting to design a cree led powered dock rechargeable torch running on 18650 cells

Hi all, I had an idea the other day that it would be very useful to have a powerful torch in my van that is kept charging in a dock all the time (as required at least) when the engine is running.I know I can get similar torches that charge via a USB cable, and that I could plug the cable into a cigarette lighter socket etc, but what I would like to do is as follows:Power from a 12v (ignition switched) source in vehicle, to a charging dock.Torch must be powered by 18650 lithium-ion cells (2 ideally).Torch would run a cree (or cree style) powerful LED chip/diode (maybe up to 10w arbitrary power).Torch does not need to have a wire plugged into it, but can be simply placed into the dock after use in order to resume charging. The connector for charging is not important but likely a jackplug type arrangement, or else spring terminals.Housing will be 3D printed, and using a lens from an existing torch (probably).So mostly I'm happy about making and designing this, except that I'm not certain about what setup (either the circuit design if bespoke or what off the shelf module etc) I should use for taking 12v to charge 2x 18650 cells in situ.I have got small USB charging modules already, and I have things like voltage boosters/reducers, and tons of electronic components, but the USB charge module is no use for using with a 12v supply etc, so I'm not sure how to best address this part of the project.If anyone has suggestions on good ways to accomplish this I'd be really grateful, thanks!

Topic by Mr Joshua 2 months ago  |  last reply 2 months ago


Can i charge 3 18650 li ion batteries in series?

I recently take an old laptop battery a part and found 3 x "packs" of 3 x 18650 cells.I disconnected each pack and i was wondering,can i charge "the pack" using a TP4056 charger?(the charging current is 1A)l;(I want to make a portable console,so i need rechargeble batteries)This is the charger that i orderd:https://www.optimusdigital.ro/ro/electronica-de-pu...

Question by AnghelutaA 1 year ago  |  last reply 1 year ago


Laptop powerbank 12v to 20v and upto 5A output using 18650 batteries with USB 5v added

Hello ladies and gentlemen.  Im looking into buying a laptop powerbank charger for my Lenovo X1 carbon that charges at 20v 4.5A 90w fast charge with upto 80% charge in 1hr. But it will also charge at 65w and maybe 45w I've read. But this will not give me the full power of the processors and gpu etc. Unless I charge at 90w 4.53A  there are are some powerbank that are around £100-170 for sale but these don't give full 4.5A. Mainly around 2-3.5A so will maybe or maybe not charge she give me full power of the laptop   so I'm thinking about making me own using 18650 batteries. Good Samsung or LG 2500maH plus cells. Prob around 3000mah.  Im thinking I could either use a buck down or step up and use the batteries on series from 3S to 8S and then 3-4P to give me around 10000mah. I'm looking for the best efficient output so I'm not sure whether to use higher input or lower input to give me 20v.  Or or maybe I could go the inveter route using a 12-24v 150w inverter?? Efficiency is the main thing here. What is the best option do you think. Should I use 12v or 24v for max effecient conversion.  Ive searched the instructables for such devices but cannot seem to find anything like this. Or would I be better to buy one??? I would want to add USB and USB c also. Defo USB 2.0.  Could you you please help me choose and find the answers please?  I fancy the DIY route because I'm looking into solar and battery power storage and also boost my range wifi range through either ptp or directional attenna. These projects will come after the laptop powerbank.  Any my help would be appreciated a lot.  Kind regards.  Scott. 

Topic by ScottL190 1 year ago  |  last reply 1 year ago


How to change the configuration of a lithium cell pack ?

I’m working on a project were I have to be able to adjust the voltage of my output by 3.7 volt increments. Example: 12 18650 batteries hooked up in series and have the voltage change from 44.4 to 22.2 to 11.1 Essential I’m trying to go from a 12s to a 3s4p or 4p3s cell configuration.

Question by prostructables 2 years ago  |  last reply 2 years ago


SnapLED powerd straight from 18650 or CR123A 3.7Volt battery?

So I don't know if you know about the red-orange SnapLED, but here is the information on it. http://www.philipslumileds.com/products/snapled#datasheets I want to power one of these with a 3.7 volt battery like a 18650 or CR123A. (or the 3Volt options) What is the most simple circuit I can use that will provide long life for my led? This led confuses me because it runs at 150ma (which is right on the boarder of High power leds) You have to treat High power leds usually more carefully than with just resistors. Will just resistors be sufficient for a 150ma led?

Question by SpiffyChee 8 years ago  |  last reply 8 years ago


glass desk piece led mod help

I found a small eagle scout glass desk piece with a black base. I'm gonna buy one and put small LED lights and a battery in the base.  I need a little help with what to do with the circuit. I have some 18650, 18650 holders, copper wire, and some down time. Should I go straight for 3.6/3.7v 18650, or should I use standard 1.5v cells? I want to do purple (my school color). Would it look better to use UV instead of regular purple? Where should I buy a bunch of little led? Online or in store? If I want to sand a pattern on the sides of the glass cube, what's the best way to go about doing that?

Topic by leaf26 4 years ago  |  last reply 4 years ago


how to test LOTS and LOTS of batteries?

We have 420 panasonic 2800mAH 3.7V 18650 batteries, which we plan to use in a solar car. I was wondering if anyone is aware of how to many of these at a time. Many of the commercial "capacity tester 18650" online appear to only test a cell at a time. This would take way too long. We need to ensure the cells we are connecting together are well-matched in terms of ESR, capacity, leakage, etc. So is there any solution that exists to accomplish this task?

Question by -max- 2 years ago  |  last reply 2 years ago


12v 18650 battery with bms but no balance. Can we use 3.7v output from it for powering bluetooth module directly?

I am trying to make Boombox Speaker. The amplifier is 12v and the bluetooth module is 3-5v input. I have a single 12v BMS module, ofcourse with 4.2v, 8.4v, 12.6v dividers. Now suppose I power the amplifier with total output, it works fine. But can I take the output of one single divider i.e. 0-4.2v for the bluetooth module sepeartely and keep using the 12v for the amplifier?

Question by SalilG2 1 year ago


Problem with OSOYOO car kit

I watch all the first part of the video and when I turn the car on the motor move a little then all trunk off. I don't know where is the problem but I know the cable are the same on the video and the battery is 18650 3000mAh 3,7V

Question by ForchettaL 1 year ago


Series Parallel 4S2P Li-Ion Battery Pack

Hey guys,I'm busy making a boombox*, my first version had an old small car battery inside which obviously weighed a tonne!Looking to make the switch to Li-Ion.I have already purchased for the battery pack:8 x Samsung 30Q Li-Ion batteries (3000mAh - 3.7V)BMS board I found online (CF-4S30A-A)2 x 4S 18650 Battery Holders.I'm unsure how to go about setting up the batteries and balance cables etc. Need the 4S2P configuration for the Voltage.I want to expand this in the future by increasing to maybe 3P or 4P (depending on how much space I'll need in my boombox).I have watched multiple YouTube videos but sick of watching 15 minutes of somebody soldering. I understand the safety aspects of Li-Ion.*I know this project could have been done with Raspberry Pi or Arduino but the rest of the guys who will use this would not be familiar with hence why I went with a Car Stereo.If anybody has any criticism, I welcome it but make it constructive!(I know I'll get a roasting for the terrible MS Word wiring diagram I made)

Question by alexmallaburn 7 months ago


modifying a mobile charger?

Hello, i have an old 2000mAh phone charger which i played with, it was supplying 3.5V.. i removed the battery and replaced it with 4 18650 batteries rated at 3000mAh each.. all are connected in parallel.. will this give me in theory 12000mAh battery? also, is it dangerous to use it or do i need to add any current limiter resistors to reduce the current..

Question by AbdullahF2 3 years ago  |  last reply 3 years ago


charging 10s5p battery pack

I'm working on an ebike conversion. I'm buying laptop batteries to take out the 18650s and put them in my pack. I'm looking at a 10s 37v pcm. If I make it in 10 sets of 6 to get 37v 14.4ah, then how can I safely charge the battery so that they don't charge unevenly in each set?

Topic by leaf26 5 years ago  |  last reply 5 years ago


Can I charge my ipod touch 4g with 9000mah? Answered

I'm planning on making an ipod charger with 3 or 2 trustfire 18650s that are 3000 mah a piece and 3.7 volts each. Could i make this work with an adafruit battery charger?  http://www.adafruit.com/products/280#Description Thank you in advance.

Question by theboygenius 5 years ago  |  last reply 5 years ago


How can I make my own usb to charge batteries then use that to charge my phone?

So I am in the field a lot with the army.... and looking to make my own battery bank.... well I was thinking of using six 18650 3000mAH batteries in a parallel and series setting. Now if I set it up like this what would I use to charge these battery?

Question by dominick.j.pezza 4 years ago  |  last reply 4 years ago


arduino powered by 3.7 volt battery?

Can an Atmega328 chip +oscillator run off of 3.7 volts without a regulator to be used for 7 channel pulse width modulation with mosfets to drive the leds? I'm desiring to power it with an 18650 battery. (which charges to 4.2 volts and drains to 2.75 volts) http://www.dealextreme.com/details.dx/sku.5790 if not, how could i do it?

Question by SpiffyChee 8 years ago  |  last reply 8 years ago


Convert 5VDC to 3.7VDC?

Hi everybody ! I'm currently working on a speaker project, and I want it to be powered by 4x 18650 3400mAh 3.7V batteries in parallel, but when they are recharged (with a separated 18650 wall charger), I want to be able to power my speaker from a wall power supply. The idea is to get the 5v power supply voltage down to something between 3.7v and 4.2v, in order to mimic the battery voltage. I already chose this one which is a 10amp-capable power supply in order to be sure to always give the speaker enough current (speaker current consumption is between 0,55 at medium volume and 3 amps a maximum volume). I first thought that i would use this board to convert 5v to 3,7v but it's only able to output 1.25 amps max so I need to figure out a way to convert 5v to 3.7-4.2v without loosing a lot of current. I've heard of low dropout regulator (LDO) but I cannot find one capable of delivering 4amps or more... Any help is appreciated ! Mahot

Question by boulou 4 years ago  |  last reply 4 years ago


Solar panel diode and battery ? Answered

Hello, I have 5V solar panel which will charge my 18650 3400mah Panasonic 3.7V battery. I will use Voltage step up to 5V and I don't know which diode should I use between panel battery? I have all these diodes. IN4148 Diodes IN4007 Diodes  IN5819 Diodes IN5399 Diodes  FR107 Diodes  FR207 Diodes IN5408 Diodes IN5822 Diodes

Question by muratm7 1 year ago  |  last reply 1 year ago


iphone external backup battery DIY with old nokia batteries as cells? Answered

I wanna charge my iphone via diy backup battery made from old nokia cells or ipad battery or even couple of iphone 4 batteries i have a step up board and a cheap backup 18650 battery board wich one should i use and how should i connect the batteries with the battery board or without

Question by turbiny 4 years ago  |  last reply 4 years ago


Circuit for power bank? Answered

Hello, Need a circuit design for the following requirement. Checked online available circuit designs but not sure if they meet all needs.  Looking for circuit design as per following details. 1. It will have one or two, 3.7 volts 2600 mah 18650 lithium batteries 2. Batteries will be charged using smart phone mobile charger or solar panel 10 to 20 volts and around 500 mah to 1 ah input 3. Will have mini usb connection for the same on pcb 4. Circuit should have battery level indication. While being charged, when they are fully charged LED should turn on indicating battery full. Also there should be one LED to show that the charging is in progress. When the battery charge drops below specific level another LED should turn on. 5. If we use 2 batteries then they will be connected parallel 6. Output voltage of the batteries should be 5 volts (so step up is required) and current should be appropriate for mobile charging 7. There should be provision for 2 USB connections. Load can be mobile charging / USB mini fan / USB mini keyboard LED (could be 2 at a time) 8. Circuit should be safe enough so no damage is caused to batteries / load etc.

Question by rahuldj 2 years ago  |  last reply 2 years ago


How to make rechargeable underwater fishing light (LED - Li-ion battery)?

Hi, I want to make an underwater fishing light with LED chips and Li-ion batteries (18650) to make it rechargeable and portable . Like this one http://youtu.be/jccC5gtD__g I do not know what should I use , which led chip and which driver ? What I need to make same light in this video? sorry, my English is bad but i'm sure you will understand me ;)

Question by Cr77777 2 years ago  |  last reply 2 years ago