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Posted

@DeepBass9 are those NiMH or Lithium cells? It is difficult to see from the picture the size (are they AA size or larger 18650) you can measure the voltage NiMH will be ~1.2V per cell and LiFe 3.7V per cell.

Posted (edited)

Thanks, does anyone know where you can just buy these cells without ordering online? Like a physical shop. Can I have some batteries please. ka-ching. And I walk out with them in my hand?

Edited by DeepBass9
Posted (edited)

maybe try these guys  (bought a replacement laptop battery from them some moons ago... finishing on the plastic was a bit iffy but battery worked as advertised).

If those are 18650's you might want to have someone with the right equipment spot weld the tabs etc for the leads... (link provided do custom packs etc).

not want to buy online? .... vape shops... but check info regarding leads/soldering etc

Edited by introverter
typo
Posted

Ha! Vape shops should sell them yes. I did not think of them. :) 
These are the same cells also used in notebook batteries and power tools. So any place that refurbish those batteries should also be able to help you.

Posted
3 hours ago, DeepBass9 said:

Where does one buy batteries like this that came out of a torch? I would prefer to just go to a shop and buy them rather than order from China. 

 

Has the torch worked hard?

If not just check their capacity first: Looks like they are connected in parallel. Charge them to 4.2V and discharge using the lamp as a load (disconnect one battery so you check one at a time). Measure the current so you can do a rough calculation on each battery's capacity.

 

Posted
17 minutes ago, Vassen said:

How are the batteries charged? Does the torch have a built in charging port? It looks like it has a tiny protection circuit to control the charging / discharging. Remember these cells become dangerous if overcharged and get damaged if over discharged. 

This is why most of the battery packs are connected in parallel. This simplifies the BMS circuit to only one circuit that protects against over voltage when charging and under voltage when discharging.  

Posted (edited)

https://www.batteryexperts.co.za/product-category/lithium-ion-batteries/

 

Try these guys stumbled across them a few months ago while searching for batteries for solar spotlights I have around the house.

Those look like they can be 18650s by the way. Same as the ones found in my solar spotlights and my vape setup but in my experience regarding vape batteries its best to stick to known brands Samsung 30qs and LG chocolates (brown wrapping) better battery life & higher output 

Edited by Gelo
Posted
10 hours ago, Vassen said:

True but i guess it also depends on the application. 

For the drill and screwdriver that i converted, 1 was a 2 cells in series and the other 4. Found that the BMS, especially on the 2 cell was not able to supply enough current and would need to be reset (connect to charger) every time the chuck got a bit stuck. 

So i simply bypassed the BMS and connected the motor directly to the output of the battery but still use the BMS for charging. If the battery pack gets discharged < 6 volts, which is still safe, the motor anyway stops. So i believe its fine. 

Outcome is revived old power tools better / lighter than new. 

In a series config these BMS circuits (on small devices) don't equalise the battery voltages of each cell.

So if one battery is kaput it will discharge first and the BMS will switch off the whole bank. You have to manually charge that cell back to the voltages of the other cells.. 

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