18650 modification

Slow Blow

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Hi, I have a great camping lantern with one rechargeable 18650 (with protection circuitry). To increase run-time, is it likely that the protection circuitry could handle another 1860 in parallel? Thanks, SB.
 

WalkIntoTheLight

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I'm not quite sure what you're asking. It sounds like you're talking about the protection circuit on the 18650 cell. But you need a protection circuit for each and every 18650 cell you use, if you want the protection. Don't disassemble one, and try to splice it across two cells, that wouldn't be safe.

If your lantern has built-in protection (such as low-voltage), then sure, go ahead and use two 18650s in parallel if you can figure out a way to get them in there.
 

Lynx_Arc

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I agree with walk, don't bother to save money trying to remove a built in protection circuit and use it on 2 cells in parallel when you can just buy a second protected cell to add in parallel. You can even use a higher capacity cell in parallel. I've seen people add a protected 18650 to a built in lipo battery in a bluetooth speaker to increase runtime.
 

lightfooted

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Eh, I don't recommend it because you seem to be relatively new to the scene.

There can be problems if you don't pay attention to certain things and they will result in bad things happening. I found a recent guide that explains the basics and why you need to be careful of what you are combining. https://batteryguy.com/kb/knowledge-base/connecting-batteries-in-parallel/

I am just saying this because Li-Ion cells have such high energy densities that caution is needed. If you were using NiMH or Alkalines I'd say go for it as the worst that would likely happen is a leaky battery...maaaybe a poof from a decent NiMH cell that overheated. A Li-Ion cell is capable of causing a serious meltdown and probably a fire from igniting any plastics in the lantern.
 
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fivemega

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Hi, I have a great camping lantern with one rechargeable 18650 (with protection circuitry). To increase run-time, is it likely that the protection circuitry could handle another 1860 in parallel? Thanks, SB.
]If mentioned 18650 has built in protection circuit, then you can parallel connect another 18650 with built in protection circuit with same capacity, same life and same state of charge. Another world, two 18650 cells both protected can be connected in parallel. Never connect unprotected to protected.
 
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