5 $ Solar Power Bank From Recycled Laptop Battery




Introduction: 5 $ Solar Power Bank From Recycled Laptop Battery

About: So basically i am a crazy person, who loves to think the most odd way ever possible,who makes what he thinks and also let other also make those . Check out my crazy projects if you like do follow me :D

As some of you know that my college was having a science exhibition , their was also a project display competition going for the Juniors. My Girl friend Meghla was interested to participate in that , they asked me what to make i suggested them this project and mentored them while making so their can be less photos as they were in a rush for the competition .

BTW this solar power bank won the contest as the grand winner of Inception 2016.

Do Congrats Them with a lovely comment. <3

Step 1: Components You Need

Here are the list of components

Tools you will need

  • Soldering Iron
  • File
  • Dremel or rotary tool
  • solder
  • glue gun
  • black tape
  • Double sided tape

Step 2: Preparing the Solar Panel

First step will be to attach the solar panel to the box for that we need to use double sided tapes.

I used 3M 's once as they are thin an also the bond is berry strong ,

You can find it in you local stores.

We drill two holes for the solar panel using our dremel.

We use a 0.8 drill bit for the work.

Then peeling off the wrap from the double sided tape we attach it to the box

Step 3: Preparing the Case for Mounting the Usb Slots

If the slots are not cut the USB in and out can't be fitted inside the case.

to make the slot we first drill a hole and then using our Dremel silicon carbide grinding bit.

take the rpm to 8k and slow grind the hole making it the shape of a micro USB.

for the USB Female slot we need a bigger slot we drill a couples of holes .

and then grind to make them joined and also bigger then by using the file we smooth it .

Step 4: About the Modules

About the charger module

last time i used a tp4056 without protection at output so that could have damaged the batteries if the where discharged below the under voltage specified by the manufacturer. the tp4056 comes with a DW01 IC which acts as a under voltage protection for the cell.

The Boost Connveter

A boost converter is a DC-to-DC power converter with an output voltage greater than its input voltage. It is a class of switched-mode power supply (SMPS) containing at least two semiconductors (a diode and a transistor) and at least one energy storage element, a capacitor, inductor, or the two in combination. Filters made of capacitors (sometimes in combination with inductors) are normally added to the output of the converter to reduce output voltage ripple.
Boost converters are easily available and they are cheap i bought a 1A 5V Boast converter.

Power input is equal to power output Input Voltage x Input Current = Output Voltage x Output Current

The Boost converter has two input just input + and input - Be careful with polarity

Step 5: Connecting Everything

Soldering the lithium Ion battery

Soldering Li-Ion may be a huge downside even for the knowledgeable techs out there.Many try and solder Li-Ion cells or phone batteries. it's not suggested by the battery makers to heat them up regardless the explanation.By victimization heat on Li-Ion cells, you'll be able to harm the plastic extractor, pressure protections or maybe the most internal metal layers.

if your hand tool takes quite an heap to heat up (30 sec +), take away it’s basketball shot favor of a diluent one. A 1mm wire tip can heat up considerably quicker than a 2mm wire tip. don't exaggerate tho'. If it’s too skinny, it'lls often.

I had to use and take away quickly to avoid harm. victimization pointed Tip is additionally higher


The Connections is giving in the diagram.

2 People Made This Project!


  • Fix It! Contest

    Fix It! Contest
  • Creative Misuse Contest

    Creative Misuse Contest
  • Metalworking Contest

    Metalworking Contest

45 Discussions

Good, I have a question, my cell will be charged instead of charging, does anyone know what to do?

Nice build! Building my own now. I have 1 question though. What is white "thing" next to micro USB? Greets

For the amount of money spent, great job. (-:


• You've been able to solder wires on the battery terminals because that one has tabs. Soldering a battery without tabs? Do not even try. Use frayed & flattened thin wire meshes under disc shaped neodymium magnets, and hot glue the thing. For 18650s I recommend ∅8×1'5mm magnets. For high currents: wrap the magnets on copper sheet.

• So-so diagram. I suspect the negative pole to the boost converter is not actually connected to the battery's cathode, or you'd have bypassed the protection circuitry (as the diagram suggests).


5 replies

Cool idea with the magnets. If I do this, I'll use that method.

I have successfully managed to solder wires to packs without tabs, but I had to sand the end of the battery to rough it up, and use a very hot iron with flux. Tinning, and preheating the wire helps. I used non-coated solid wire (that can be left on a heat source to keep it warm) to join them, and cover the joints with hot glue to protect the ends of the battery afterwards.

I agree with you. Soldering is not a good choice, but it can be done, if one takes the time to prep the metals, and works fast so the battery wont overheat.

Thanks You
What is the tabs actually ?

i took the output from the tp 4056 module , from the protection pins,

the diagram was made for the competition and i didn't remember to change those.
thanks for showing it.
i will update it soon .

Laptop pack pulled batteries usually have spot-welded tabs.

Now that I'm seeing it more carefully your battery only had the cathode tab (-). The tabs are those “fins”. :-D

A correct solder joint is performed by steadily joining the surfaces to be soldered and then uniformly heating the joint with a pre-tinned soldering iron tip (heat transfer surface maximization); when all the surfaces reach fused solder temperature, solder flows easily and the joint is well done if cooled in a stable way (i.e. do not shake the stuff). If the surfaces to be joined do not reach solder temperature, a fragile cold joint will result (and it'll break sooner or later).

Check the photos. (-:

Hope it helps.



Hi, a small tip is not a good for soldering 18650, because you get worse heat transfer (less surface area) and a big tip acts as a thermal capacitor.

Soldering direct to tabs is doable but needs to be done very carefully. You first tin the taps with a HOT big iron and 10-ish seconds. Then I use tinned solder braid as my connection. Again very few seconds (absolute minimum.) Between tinning and soldering allow cell to fully cool.

5 replies

Dear friend,

Good work. i just want to know

1) the life of solar panel what you had used.

this is epoxy mini solar panel.

2) also some the li-ion 18650 battery are available with PCM/PCB (for cutoff for low discharge & overcharge protection circuitry ) then we don't want to use tp4056.

attached image shows li-ion with PCM/PCB


Thanks For the pic

Unfortunately i don't know the lifespan i bought that on ebay , where it was not written .

if your has inbuilt protection you can use that only just get a USB break out for the connection.

thanks for replay. i just want to know through 3V to 5V boost converter can we use total charge from 2.2Ah battery to charge our mobile?

If you're an electronics guy, think of the big iron and heat as a higher RMS current, allowing faster localized heating. If you're not an electronics person, or just dislike the metaphor, ignore my side point :p.

In all cases, you want heat getting in FAST and you want to avoid buildup to the max. Endless-sphere.com has a 50+ page thread about making battery packs from 18650 cells, tho most ppl making a big pack invest in a cheapo capacitor spot welder.

The thread has great info about sorting cells too, since especially if your source stop is crappy recycled cells you really want to get the good ones. As much as more would seen always better if you tolerate weight and size, any cells with self discharge are particularly important to exclude from your pack


2 years ago

Nice Work Congrats to the Winners. I'm interested in trying to make a Solar Panel so I can see if i can make them for my Home Any Suggestions? ?

3 replies

yes you can do that in my next coming project i would make one Home only. Stay tuned :D

I use electricity for only 1 CFL lamp, one table fan, plug to charge mobiles. I want to use solar . Let me know if you have a product. rrmuraliramsamy@yahoo.com

Yay for reduce, reuse, recycle! How long does it take to recharge a cell phone, from the SolarBank?

1 reply

500 ma that is around 4-5 hours for 2200 battery phone