Recycle Laptop Batteries - 12V Power Wall/Box! 回收筆電電池 - 12V電源牆/盒!




Introduction: Recycle Laptop Batteries - 12V Power Wall/Box! 回收筆電電池 - 12V電源牆/盒!

About: I'm a maker and engineer... I make mad stuff... check out Dubious Engineering on YouTube

I have become a little green in my old age...

Recycling old stuff is good fun... but, as with most of my projects, please be careful! - This one makes use of Litium Ion batteries which can explode and catch fire if mis-treated! (I have demonstrated this in a couple of my YouTube videos!).

This instructable describes in detail all the necessary steps to make your very own high-capacity power box for powering lighting, sound systems, soldering stations, etc... Mine has over 100 x 2000mAh 18650 batteries in it!

Each battery is individually fused and connected to a BUSBAR to ensure an element of safety.

There is a protected missile switch fitted and insulated terminals are fitted.

Charging should not exceed 12.6 volts and depletion should not exceed 9.3 volts.

I have created a series of YouTube videos which really help describe the whole process. Please subscribe to my instructables page and subscribe to my YouTube video channel to see more interesting projects!


回收舊東西是很好玩的...但是,像我的大部分的研究項目一樣,請務必要小心! - 這項目是使用鋰離子電池,如果處理不當可能會引起爆炸和起火! (我已經在我的幾個YouTube視頻中展示過這一點)。

在這instructable上詳細描述了所有必要的步驟,讓您可以做個自己的高容量電源盒為照明、音響系統、電焊台等供電...我的電池有超過100 x 2000mAh 18650電池!




我做了一系列可真正幫助我描述整個過程的YouTube視頻。 請訂閱我的instructables網頁,並訂閱我的YouTube視頻頻道,以利查看我更多有趣的項目!

Step 1: Extract 18650s From Used Laptop Cells

Using some large adjustable wrenches, put opposing twisting pressure on the laptop battery in order to encourage the moulded seal to break giving you access to the internals of the battery.

Then, carefully remove the cells, using cutters, remove the charge management PCBs and any wires.

Clean the batteries and test them for voltage with a multi-meter. The voltage should be between 2v and 4.3v if the cell shows lower voltage then 2v it is likely broken and should not be used.

Step 2: Create Tesla Style Battery

Strip some solid copper wire from some household cable. This will be used as a busbar.

Find some thin wire (perhaps 7 core bell wire) strip the sheath and twist together two of the cores. This will become your fuse wire.

Find a decent, hard-wearing box that will fit your batteries.

Align a set of batteries that you want to connect in parallel, solder the negative terminals of all of the batteries together using a busbar. Solder small filament fuse wire (made from bell wire) to each positive terminal of each battery. Then connect all the terminals in parallel with a bus bar. (Please see pictures).

Make three sets of these blocks of parallel batteries. We will connect all of these in series to generate the 12v. Again, please see pictures.

Step 3: Fit a Meter and Terminals to Box

I chose to fit a missile switch (so the box wouldn't be accidentally activated) and I purchased some insulated 4mm banana jacks and a 12v LED meter from eBay.

I then went ahead and chose appropriate places to fit the switch and connectors.

Once fitted, I wired them in place as shown in the circuit diagram - next page!

Step 4: Connect Everything Up and Start Testing

As per the circuit diagram, connect everything up and run some basic tests with the multi-meter. Check the voltage of each pack and finally check the output voltage of the system. Connect in-line the switch and the output terminals.

Step 5: Using and Charging

Do not charge at more than 3 Amps

Do not charge more than 12.6 Volts

(I use an iMax charger as pictured)

I plan to add a solar charge circuit to this in the near future. But for now, this unit is very useful and as such continues to get used!



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    15 Discussions


    9 months ago

    Mixing cells with different chemistry isn't allowed

    2 replies

    sure, but but have different chemistries, if you understand what I mean! What I saw in pictures, mixed 2 of 3 battery cells types, CGR with INR and I guess also with ICR

    Hi....with this type of connection (battery like 1+1+1+1....) the first(or the last)

    battery have big stress!! is beter if you connect like "x" style....the first battery connected with the second and the third, the second with the first and fourth..etc etc....every battery is connected with 6 other battery(for eliminate stress charge and discharge an problems in case one battery is "out")....

    with your mode of connection,in case one battery is dead,all package is compromitted.....(interruption of electric current and danger of explosion bicause the battery dead can become like a resistor.....).....

    yes i know...the BMS is too expensive.....bat you can copy the connections styles....


    1 reply

    Thanks for your feedback... I will limit the current to avoid danger ... 5A

    Looks nice and I"m sure it functions well. But that design is a real serious fire starter. You can't put that kind of load on the last cells without a massive amount of Heat being generated and the level of charge provided. IT WILL EVENTUALLY OVERHEAT AND THEN EITHER CATCH ON FIRE OR EVEN EXPLODE. ITS VERY DANGEROUS,

    1 reply

    But they are all in parallel... 3 banks of 30 in parallel... and I don't plan to draw more than 5A


    because it is a Dangerous design without charge control

    1 reply

    I have some BMS modules ... but my charger has ability to manage this. As it's a simple low current unit 5A max I'll consider your suggestion for the new system for my shed power!

    Yes , looks nice , but perhaps hole vents are needed and wood is a little dangerous...perhaps fireproof plastic like electric connection box or similar are better choice ( or metal ) and adding one magnetothermic rated at 40/50 A will increase overcurrent protection (instead a missile switch) ....and add charging balancing cells (BMS) for increase the life hope of the system.

    The proof of the concept is good , anyway.

    Cheers !

    1 reply

    Thanks ... I have limited myself to 5A current which I hope means we shouldn't see and fire!! :-)


    9 months ago

    Bummer with the bad feedback. I understand doing that and I appreciate that. But I sure wish you guys post up an example of a proper setup. Cause I'm interested in something like this for a small DIY RV.

    1 reply

    Understood... there are a lot of people making power walls on YouTube... have a search around...

    Your build is fine all but the buss bars, You need to make them bigger that can support the combined current of your cell group. For the number of cells you have, I would use 2 pieces of 10 Gauge copper wire soldered parallel on each cell group. You don't really need a charge controller as you are charging with a hobby charger, but I would use the balance mode with that.

    Think about what current each cell can output, then multiply x cells, this is what your bus bars need to handle along with the wires connecting between cell groups etc. Plan for the maximum even if you never use that and you wont go wrong. Also consider an automotive contactor switch to pass the current and use the smaller switch to work the high current contactor. All in all your design is fine, and hope my input is helpful. :)

    1 reply

    Very helpful!! Must admit this will always be under 5A but I may make another in the future that supports my workshop and then I will actually design it instead of bodge it!!