Differently Sized 18650 BATTERIES

[GaryH]

My Ultrafire 18650 batteries have to be crammed into my Ultrafire charger which puts a dent into the positive terminal. Ive now seen that these batteries are a bit longer than my Solarfore 18650s which fit nicely into the charger. Does anyone have any explanation for the different sizes please.



Many thanks



Gary

 

[buwuve]

A 18650 should have a length of 65mm. Often they are longer, because they have a protection or the manufacturer use cheap cells, which are bigger.

 

[HKJ]

My Ultrafire 18650 batteries have to be crammed into my Ultrafire charger which puts a dent into the positive terminal. Ive now seen that these batteries are a bit longer than my Solarfore 18650s which fit nicely into the charger. Does anyone have any explanation for the different sizes please.

This has to do with the protection circuit, you can see how it is mounted in my Anatomy of a Protected Battery.


I have collected a list of 18650 batteries and chargers with length (It is more like reviews).

Note: There are links, but they are not very visible before Greta has fixed some setting.

 

[GaryH]

Thanks very much.

 

[tobarger]

This has to do with the protection circuit, you can see how it is mounted in my Anatomy of a Protected Battery.


I have collected a list of 18650 batteries and chargers with length (It is more like reviews).

Note: There are links, but they are not very visible before Greta has fixed some setting.

Once again
Thanks HKJ for the very clear informative links with wonderful pictures

 

[45/70]

Just to point out that most 18650 cells are about 65mm in length, as they should be. As HKJ pointed out, it is the protection circuit that has been added on by third parties that increases the length of these cells.

Li-Ion cell manufacturers do not produce cells with protection circuits added. Therefore, if cells are 65mm to start with (again, as they should be), they are going to be longer when a protection PCB is added to the bottom of the cell.

Dave