Can I use a cell phone to charge any 3.7v li-ion battery?

I want to use a cell phone to charge 3.7v li-ion batterry that are shaped like a AA (same as laptop batteries)

Question by Sincere 9 years ago  |  last reply 9 years ago


Li-ion

Does anyone know how i can make the lithium-ion for my laptop last longer, if you have any ideas of suggestions or ideas please tell me!

Topic by rickick 12 years ago  |  last reply 12 years ago


Rechargeable Lithium Ion Batteries

Hello Everyone! I am planning to make a rear bike light, which has rechargeable batteries through USB. I then decided to use Lithium Ion Batteries for it. But the problem is that I dont know what parts I need. It should be able to light up 4 COB LEDs (Each rated 12V, photo given) Till now, after looking at several other instructables, I am able to say that: 1. It needs a steup transformer from 5V TO 12 V - TP4056 (https://www.amazon.in/TP4056-lithium-Battery-Charging-Charger/dp/B00JQ2VG1A/ref=sr_1_8?ie=UTF8&qid;=1505148914&sr;=8-8&keywords;=lithiumion+batteries)  or https://www.adafruit.com/product/259 2. It needs some sort of protection like:  http://www.batteryspace.com/PCB-for-11.1V-Li-Ion-Battery-Pack-4.0A-limit-----PCM-L03S04-559.aspx 3. Also do can I allign three 3.7V Lithium Ion Batteries to make 11.1V? Please help me out Thanks!

Topic by nabeel.quadri 1 year ago  |  last reply 1 year ago


Reconditioning Lithium Ion Batteries

I'm looking for a DIY method for reconditioning Lithium Ion batteries. Or, if that's not easily doable, someone who knows to tell me so i can just bite the bullet and buy a new one. Thanks in advance!

Topic by royalestel 11 years ago  |  last reply 2 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


Cheap Lithium ion batteries - help?

I picked up 4 Canon NB-4L batteries for 50p each, thinking that for the price they might be worth having. However, I don't have a charger - any help with this? I've got power and electronics and stuff. 3.7V 760mAh (Li-ion)

Topic by lemonie 9 years ago


Leave LI-on battery turned on?

Hello! I bought a li-on battery ( http://m.ebay.de/itm/281697770691?varId=580703135130) and it has this little switch. I want to build a boombox and dont want to open it everytime to turn it on or off. I also dont want to rip the switch appart because i sind want to destroy the batterypack. Can i leave it turned on and place a switch between the circuit and the batterypack? Or will i destroy it if i leave it on all the time?

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


Lithium-ion batteries for electric car?

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


HELP please!! with Li Ion battery

1 st question: i have a 7.4v 2200mA li ion battery. my ip camera takes 5v 2amps what color resistor should i use and how many ohms? 2nd quesiton: i have a class 2 battery charger 12 volts 300mA is it good to charge my 7.4v li ion battery?

Question by dwstar79 7 years ago  |  last reply 7 years ago


Highest capacity Li ion 32650 and 26650

We now have the highest capacity Li ion 32650 3.6V 5500mAh, and 26650-4500mAh, 500~1000mAh higher than most in market. if anybody is interested, please contact us by ruy@gebattery.com.cn

Topic by Ruy Liu 9 years ago


Battery recommendation

Hello, I'm looking for a rechargeable battery for a project and I'm not having any luck finding a suitable one.  Here's what I need: The battery will need to be between 12 - 18v with between 1-2 amp.  This will be powering a set of speakers, so not really sure what type of amp hours I need.  The battery will need to fit into a tin lunch box.   An idea I had was to use a 12 or 18v battery for Power Tools - not sure if it will work though.  I also found this, http://www.altex.com/12V-Lithium-Ion-Rechargeable-Battery-Set-LBP-124500-P150057.aspx not sure if it is powerful enough though. Any thoughts/ideas is appreciated.  

Topic by RabidNoodle 7 years ago  |  last reply 7 years ago


Lithium ion battery capacity calculations?

     I'm working on a project that uses lithium ion batteries as the power source and cannot figure out how to calculate how long it will run for.  I have four 2.6Ah batteries connected in parallel, giving me a total of 10.4Ah of capacity.  They're lithium ion so the nominal voltage is 4.2v and the minimum I want to bring them to is 3v.  My project draws a constant 2.85W of power, regardless of the voltage put into it.  What I want to know is, is there any way to calculate or even just approximate how long these batteries will power my project before they run out (the voltage drops below 3v)?  The batteries are high quality, so the 2.6Ah rating is pretty reliable.  Let me know if there are more specifications needed or something.   Thanks ~Dudes

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


Lithium Ion battery for CPAP machine?

I'm trying to figure out how to power a CPAP machine (this one) for a few nights of backpacking/camping. Does anyone know how to hook it up to a lithium ion battery (and what type to get) with out forking over all my money to the medical supply industry? I'm dying to go backpacking for at least a night or two. any help would be appreciated.

Question by nickbakes 7 years ago  |  last reply 7 years ago


Lithium Ion Battery Shut Off

Hi, my name is Jackson Pugliese, and I am currently building a battery pack that will be consisting of multiple lithium ion batteries. Getting the pack itself together, is not an issue at all, however, what is an issue is battery shut off when charging.  I would like to be able to charge my battery pack with some form of laptop charger, that outputs 12v, for a 14.8 volt lithium battery pack. The main issue is overcharging. Lithium ions explode, or catch fire if they are over charged, and thus is not an option for me, so to find a solution, I searched the internet, and two things came up.  Option one, use some form of battery charger, that automatically shuts off when It is fully charged (which i do not want to do because I want to do it differently hence the instructable) And Option two, which came up alot, but i do not fully understand is I use something such as this  http://www.amazon.com/Yeeco-Current-Polymer-Lithium-Protection/dp/B010NM52LG/ref=sr_1_2?ie=UTF8&qid;=1456701414&sr;=8-2&keywords;=protection+circuit+module+14.8+volt I do not understand what it truly is, nor how to use it, and would like someone to explain to me both of those things. Everything I am doing is safe, because I am using a en closer for lithium ions, in case if they explode or catch fire, so know one has to worry about anything not working. Thank you very much everyone for your time, and have a wonderful day!

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


What are the pros and cons of lithium ion batteries (besides cost)? Answered

Question by loki17 8 years ago  |  last reply 8 years ago


is there a way to "fix" a li-ion battery that wont take a charge?

I have an older (dell latitude c400) that works great, its tiny and weights only about 4 pounds. I got it 2nd hand about a year ago, ever since I got it the battery shows no charge even when the laptop is plugged 24/7. Is there a way I can "zap" the battery or something like that?? I've seen instructables about zpping nicad batteries but nothing about lithium ion ones... Any and all help will be appreciated.

Question by orallo 10 years ago  |  last reply 10 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


DIY battery setup help

Hi, I'm a first time DIY-er and would like to build a useful, long lasting battery pack for my *new* laptop (late summer). I'm 17, and this would be a perfect project for me to finish in the next few months. I'll be working with my dad and asking my physics teacher, who seems very all-knowing, for advice. My teacher understands electricity and batteries better than anyone else locally and is leading our STEM team, of which I am a member and need this experience. Keep in mind that I'm not just doing this to have a (much needed) battery pack for my laptop. I got most of my information from here and will most likely be purchasing new batteries. As far as the housing of the components, I have a hard plastic, 10+ year old lightly used blue lego container in the shape of a kid-sized briefcase.  Case: Old blue lego carrying case, 11” x 7.5”(9 including curved  front) x 3.5” Insulation tape Batteries: (x4) Battery holders: (x4) PCB: (protected voltage is higher, balance charger required) Balance Charger: Fuel Gauge: DC port: Wire terminals (for organization) Balance charge cords: Optional inverter: I heard about these being inefficient, so I'm not sure about it. Please inform me if there are any other parts that I'll need or if I've left out any information. Also Inform me if everything I'll need for a lithium battery pack is on this list. P.S. The case was chosen based on the fact that it will fit in my backpack with my books and looks much less alarming and more like a DIY battery than a black box or briefcase. especially with the fuel gauge and plugged in laptop.

Topic by leaf26 6 years ago  |  last reply 6 years ago


Why is it so hard to find lithium ion rechargeable AA, AAA, or other standard battery sizes in lithium ion? Answered

No real details here just though it would be nice to get standard battery sizes in lithium ion rechargeable instead of nimh.

Question by robbtoberfest 9 years ago  |  last reply 9 years ago


ReHab for Li-Ion Batteries??

Is it possible to get more life out of Lithium Ion batteries that no longer hold a charge? These things are great when new, but for the cost, they seem to crap out in a yr or 2. Specifically, 18v Ryobi cordless tool batts.

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


Piggy Backing a lithium battery (cell)

I have several questions.  But the basic idea is that I want to extend the runtime of a device (such as a cell phone, tablet, camcorder, whatever) by increasing the mah.  So here are the things I am wondering: 1)Many lipo batteries have 3 or 4 contacts, one is -, one is +, and the others are typically data or something.  can I simply connect additional lipo's (just the + and the -) in parallel with the corresponding contacts in the device? 2) Are there any ill effects of charging (presumably from the built in charger of the device, like a cell phone) and discharging (using the device) parallel lipo's? 3)  They will all have the same voltage rating, but do they all have to have the same mah rating? thankyou

Topic by guyfrom7up 8 years ago  |  last reply 8 years ago


How should I recharge a 7.4V battery? Answered

I have a 7.4V rechargeable battery and I'm wondering what voltage I should be charging it with. would 9V work? Are there any general guidelines for recharging batteries? Specs: 7.4V 1400 mAh Lithium-ion Was originally used in a NXT LEGO robot. Thanks! Ryan

Question by jensenr30 7 years ago  |  last reply 4 years ago


How to make a battery charger?

So I was just wondering, what basic guid lines do you have to follow when making a battery charger for say a lithium-ion battery? How many volts do I need to supply to it? Do I need any protection diodes? How would I keep it from charging to fast, or trying to charge the charger? Thanks!

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


Charge 4 Lithium Ion Batteries in series?

I have got 4 3.7v 6000mAh lithium ion batteries connected in series with 2 batteries holders. I would like to charge them without taking them out (prefer to seal a unit). Anyone know how to do this (I could connect the 4 "cells" individually to separate input/outputs.)? Also have 19v 3.16A power supply available to use also for charging (Batteries are for making it portable and plug for the 19v) Have this ordered if it is useful: 4-Cell Li-ion Li-Po Lithium Battery 18650 Charger Protection Board Help appreciated

Question by bonze77 3 years ago  |  last reply 3 years ago


IS it Logical to use Lithium ions in noramal cars?

Just Normal cars,not electric ones..I think it may not be able to charge and discharge at the same time for Lithium family..Am i right? pls  point out some faults..that you think may occur?

Question by Nr-Think different 6 years ago  |  last reply 6 years ago


Lithium ion battery help: please read Answered

I have question about lithium ion batteries. I do a lot of electronic work (both school and hobby) and I have never really learned about these batteries, I do know the basics but what i want to know is, if I replace a lithium ion battery with another, same voltage and maybe higher mah, but higher capacity would there be any risk? I want to add a higher capacity lithium ion battery to one of my projects but fear any bad outcome. any info would help a lot! I would still be charging the battery with the same voltage and discharging. so the only thing changing would be the battery size. does this pose a risk? I think the answer would be no risk but i feel as if its better safe than sorry.

Question by out-of-the-box 6 years ago  |  last reply 6 years 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 3 years ago  |  last reply 2 years ago


Modify this circuit to make it lower voltage? Answered

What resistors do I change in this circuit to make it go red at <3.2V and green at >3.2V ? It is a battery monitor that uses op-amp, 2.5v voltage reference diode, and a 2-pin bi-color LED. The trimpot adjusts the voltage at which the colour changes. http://i48.tinypic.com/28qtb3l.gif

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


Solar??? Batteries??? controller???

I want to get these 12v solar battery chargers they come with alligator clamps to hook to the battery. i want to get enough for around 150 volts so how would i hook the solar panels in series, and do i need a controller for each battery? and how would i rig that up and how can I get it going into all the 12 volt batteries without any damage to the batteries etc. And can this be done for less than $400 if the solar panels are $30 each and the batteries are $14 each. THANK YOU!!!!  THANK YOU!!!!  THANK YOU!!!!  THANK YOU!!!!  THANK YOU!!!! oh and could you give me links for all the stuff I'm gonna be buying. THANKS!!!!  

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


Questions on building a lithium battery pack with pcb?

I have to build a pack to run my portable N64.  I have some experience building with NiMh and NiCad, but I havent built a li-ion yet. Ive done my research but would like some feedback before I start building. Parts 18650's - 3.7V  3600mAh ea 7.4V PCM for 18650 Li-Ion/ LiPo 7.4V Li-ion/LiPo charger at 1.2 Ah Plan Either to build a 2S2P pack or a 2S4P pack.  Currently the N64, 7" TFT LCD, Controller, and Audio amp w/ 2x 8Ohm speakers is consuming just over 1A from what i can tell.  its running off of a perfboard w/ regulator and rail, thats hooked up to a universal transformer that is set to 7.5V  1A.  Everything works but when I turn the volume up it cuts off and then powers back on.  I dont know any other way to find out the over all power consumption.  I cant just look up all the specs because the LCD is from china and i dont have any specs. Anyway, back to my plan.  obviousely I want as much run time as i can get out of it with out compromising weight and space.  all componants of the portable can run off of 7.4V or lower, to include the lcd even though its rated at 12V. it can run as loas 6.5V. I have been debating between the 2S2P which should yeild 7.4V 7.2 Ah, and give me a runtime, some where in the ball park of 4 hours. or a 2S4P which should yield 7.4V 14.4 Ah. It would only be slightly more space and provide approximately 8 Hours+ Thats if I am even calculating everything right Ok, Regardless of whether i run a 2S2P or 2S4P the connections to the Protection Circuit will be the same, Right? Pos --> B+ Neg --> B- + to - ( Between Series connection) --> B1 or BM I understand that Li-Ion are safer when it comes to balancing then LiPo, but is this right?  having 2 parallel cells or 4 parallel cells connected with the only balance connection between the series.  I just want it to be safe. Next  is the charging.  I bought a cheap smart charger for 7.4V 1.2A output.  Will it matter whether i build the 2S2P or 2S4P, or will it work for both.  I know it will obviousely take twice as much time to charge with the bigger pack, but is their a max number of individual cells that a PCB can handle, or does it only matter the overall voltage? I also Included in my diagrahm a setup for a DPDT switch to change between pack powered, wall powered and battery charging.  I want it to have an "ON" and "OFF" setting. while off, pack is disconnected and if wall charger is plugged in, it will charge the pack.  while in the "ON" position, pack will power the device, but if wall charger is plugged in, then it will run off that. Can I even use a wall charger for the Li-Ion pack to power the device, or will it not work.??

Question by supramp 7 years ago


Why the cordless drill motor not run?

Hi all, I have a problem with the motor of the cordless drill. I converted my cordless drill from Ni-Cd battery to Li-ion battery 12v6 using the protected PCB as this image: http://www.ultest.com/shop/image/cache/catalog/Power-Modules/HX-3S-A01-1-500x500.jpg. After connecting the 3 cells Li-ion battery to PCB, I measured the voltage at P+ and P- is 12v. So the connection between the battery and PCB is correct! Try to connect P+ and P- (from PCB) to the positive and negative terminals of the motor, then the PCB cut-off voltage at the output pin. The reason is the 2 terminals of the motor is connected (using the Digital Multimeter to check). How to resolve this problem with the motor working properly? Thanks. Sy Do

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


what is so hard about charging a lithium ion battery? Answered

I am making a wind turbine charge my cell phone. my design will use a hand made wind turbine using an electric motor. hooked upto a 5v voltage regulator. with some capacitors. if it is putting out 5v i know it will charge right? i heard of batteries messing up.  i will constantly monitor the phone too see when it is charged..according to my phones battery indicator

Question by ismael01 7 years ago  |  last reply 7 years ago


charging lithium ion battery with solar instead of lead acid battery?

Iam using a 6v, 4.5ah lead acid battery to power my 6 leds each of 0.20 watts for around 10 hours . also i am recharging the battery with a 5 watt solar panel . now i want to switch to 3.7v, 5.2ah lithium ion battery. will it work ?

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


whats so hard about charging liithium ion batteries? Answered

I am charging my cellphone. its an android. the charger for it says the output is 5v 700 mA. i am using a  wind turbine or solar panel or both connected to a 5v regulator. and some capacitors. should work right? i will keep a close eye on the phone checking the phones battery indicator to see when it is completely charged to avoid overcharge

Question by ismael01 7 years ago  |  last reply 7 years ago


Hi, why cant alkaline batteries replace lithium- ion? Answered

Question by led235 9 years ago  |  last reply 9 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


How to Make a Constant Current Lithium Ion Charger

Hi Guys! I have a bunch of 18650 lithium ion batteries that can handle a charge rate of 5C. Each one is 3,000 milli-amp hours, and I would like to build a charger for them as my project. I understand the mechanics of charging lithium ion batteries, and that they need to be charged at a constant current up until that current reaches 4.2 volts, than switch over to constant voltage. The constant voltage charging makes up about 20% of the battery capacity, and I am willing to forgo that amount. What I am trying to build is a constant current charger for it that would  charge at a current of 1C, and shut off when it reaches 4.2 volts, and I would like some help as to how I would do this. I was thinking that I would have some sort of current source that supplied 3 amps and then have a relay that would shut off the current as soon as a voltage detector reached 4.2. I do not know much about current sources, so I am asking here for some help. Thank You for Your Help!

Topic by merlinj 2 years ago  |  last reply 2 years ago


Managing high-voltage lithium-ion batteries in HEVs

From EDN (Electronic Design News), comes this article: Skyrocketing energy prices and the growing concern over carbon emissions have focused attention on electric and hybrid-electric vehicles. New lithium-battery designs will be key technologies for efficient EVs and HEVs.By Michael Kultgen, Linear Technology Corp -- EDN, 4/9/2009Safely getting the most energy and lifetime from a lithium cell requires some sophisticated electronics. One requirement, for example, is the ability to measure the voltage across every 3.7V battery cell in a stack of 100 series-connected cells. How do you cope with the 370V of common-mode voltage and reject 100V of common-mode switching transients? The design of battery-management systems for EV (electric-vehicle), HEV (hybrid-electric-vehicle), and UPS (uninterruptible-power-supply) applications requires solving many such problems.How do batteries make cars "green," ...http://www.edn.com/article/CA6648791.html?nid=2432&rid;=8848980

Topic by Goodhart 10 years ago


LED torch lens?

I have this LED torch, a luxeon 'MXDL' (next to a AA battery in the photo). It's a 3 watt LED torch (supposedly) running on a AAA battery connected to a joule thief of some sort (it has some sort of transistor, a capacitor, and an inductor), but it isn't that bright,( being about the same as a 3 5mm LED torch which has these lenses), but I still like it because of its compact size and light output. Anyhow, its throw is kinda poor, and I was wondering whether I could put a cheap lens onto it (from out of, say a camera's lens) to increase throw. Would it work? How would I go about it? P.S: I found these AAA li-ion batteries online, but I didn't even know that those batteries existed. If I put one of them into my torch, they'd probably increase brightness a lot, but because they are only rated at 300mah, I really doubt if it would be worth buying them. What do you think?

Question by .Unknown. 9 years ago  |  last reply 8 years ago


Strange battery charging idea.

So I have an Idea for a charger for a portable computer.  It will be solar powered, and charge li-ion batteries.  My question is how could I simultaneously charge batteries and power the computer at the same time.  No schematics are needed, just a quick written answer. Thanks!

Topic by Skiboy941 7 years ago  |  last reply 7 years ago


Know of a cheap 24v li-ion to run a boom box?

Hello, I've been building boom boxes of various sizes using 24v amplifiers. I can never find medium sized 12v class d amplifiers, so I am forced to used 24v. My favorite amplifier is the tk2050. The inexpensive li-ion cctv batteries I use for my 12v amplifiers can't be used in series because the internal circuitry seems to cut out.  Can anyone help? Extra points for simple, cheap, light. Something around 7 Amp/hrs would be great. Maybe under $30. Oh, and how would you charge it? Thanks!!! Tor

Question by torclausen 6 years ago  |  last reply 3 years ago


AA Battery replacement

Hi, So I have a AA battery pack inverter for some EL wire, and I was wondering if it was possible to replace the AA battery's with a lithium Ion battery to reduce its size. What kind of voltage should I look for/do I need to take into account amperage?

Topic by Fozzibehr 5 years ago  |  last reply 5 years 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 8 months ago


do the protection circuits in batteries handle charging too?

Do the protection circuits in rechargable Lithium Ion (and etc.) batteries stop the battery from charging once its fully charged? im just wondering because i plan to repair a palm pilot that cant charge on its own.

Question by zack247 7 years ago  |  last reply 4 years ago


Why can I recharge lead acid batteries with solar but not lithium ion?

I just got a 5 watt solar panel and started experimenting with it today.  I want to use it to charge a single 10 watt hour/2.5 amp hour 18650 lithium ion cell.  The solar panels have an open voltage of 22 volts.  I connected the solar panel to an anyvolt3 (boost/buck power regulator), set the anyvolt3 to put out 4.2 volts, then connected  the anyvolt to the lithium cell with a blocking diode.  I accounted for the voltage drop of the blocking diode and the panels charged the lithium cell at .1 watts.  Pathetic. Then I tried charging a 20 amp hour Werker sealed lead acid 12 volt battery.  I set the anyvolt to 14.4 volts.  The panels charged the lead acid battery at 4.5 watts.  Thats pretty good.  Now why can I charge the lead acid but not the lithium.  The lithium is what I really want to charge because i want to use the solar panel to charge lithium cells when I go on long bike tours.  I don't want to take any heavy lead acid batteries on my bike trip. Thanks

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


USB Charging Circuit for 3x 3.1V Lithium Batteries

I am trying to make reliable charging circuit using 5V(USB) as source. With it I aim to charge 3 Li-Ion batteries - small coin batteries(MS621FE, datasheet). How can I make such a circuit with:  - light indication (LED)  while charging  - light indication (LED) for fully charged that stops the first LED  - protection against overcharge There are a lot topics covering similar circuits but all of them are at least for 3.7V batteries which is dangerous for such a small battery (suggested charging voltage between 2.8V and 3.3V). Does anyone have any idea how to make such a circuit?

Question by UnitedMind 4 years ago  |  last reply 4 years 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 3 years ago  |  last reply 2 years ago


why do all batteries require different charging? Answered

I mean like the difference between nimh, lead-acid, lithium-ion, and recently even alkaline. how do they each charge, and why is there a danger of exploding batteries (like lithium-ion) when charged the wrong way. is it like charging in fast on/off cycles, high volt low amp (or the other way around) or messing with anything else?

Question by godofal 9 years ago  |  last reply 9 years ago


why won't my xbox 360 wireless controller recharge?

I bought 2 AA lithium ion batteries for the controller and i expected that when i connected it via the usb cable that is used to charge the xbox controllers with the rechargeable battery pack that it would charge the lithium ion double A's. why doesn't it charge them? when i insert dead AA batteries and then put the charging cable on the batteries heat up because (i presume) that the cable is trying to recharge non-rechargeable batteries. so if it will recharge rechargeable battery packs and attempt to recharge non-rechargeable batteries why won't it recharge lithium ion double A's?

Question by cdubnbird 9 years ago  |  last reply 9 years ago


waterproof battery pack for 2-3 Li-Ion Rechargeable 2032 Button Cells

I need help making a waterproof battery pack for 2-3 lithium ion rechargeable button cells.  I want to run a strand of 10 led chrsitmas lights on button cells rather than 2 AA batteries.  please help. jtr10@netzero.net Thank you for your time Jeremy

Topic by jjrat10 7 years ago