18650's - Is this safe?

[Chippy_boy]

I am getting a new Thrunite TN32 on Monday - very exciting

However, I don't have 3 of any 18650 batteries. I have a couple of Enerdan 18650 3400mAH's which I believe are protected Panasonics. Plus some other Xtar 2600mAH protected 18650's.

I have ordered 3 more of the Enerdans but they ship from Germany and won't arrive for a week or so. In the meantime, can I run my new TN32 with 2 of the 3400's and one 2600 battery? I don't want anything exploding! If not, is it at least OK to try it out for a few seconds, just to make sure the torch is working OK?

Thanks

 

[moldyoldy]

I am getting a new Thrunite TN32 on Monday - very exciting

However, I don't have 3 of any 18650 batteries. I have a couple of Enerdan 18650 3400mAH's which I believe are protected Panasonics. Plus some other Xtar 2600mAH protected 18650's.

I have ordered 3 more of the Enerdans but they ship from Germany and won't arrive for a week or so. In the meantime, can I run my new TN32 with 2 of the 3400's and one 2600 battery? I don't want anything exploding! If not, is it at least OK to try it out for a few seconds, just to make sure the torch is working OK?

Thanks

Condition: Ensure that each cell is fully charged and independently verified with a DMM. Then it is OK to use the cells described above to briefly test out the light to verify operation, but absolutely no run time of multiple minutes.

My basis for this:

Enerdan is based in Berlin and uses quality cells from Panasonic, Samsung und Sanyo and adds protection to each cell intended for consumer usage. Quote from the Enerdan website (which mainly states what I said above):

"Mit unseren OEM-Akkus Li-Ion 18650 konfektionieren wir die industrielle Zelle, sodass diese mit PCB im Consumer-Bereich verwendet werden darf."

Even Enerdan is careful with it's permissions in using only protected 18650 cells for Consumers!

XTAR is a mixed bag. Their current 1850 2100mah cell is unprotected. It appears that their 2900mah cell is protected, but I cannot confirm that perception from the XTAR website. The 2600mah cell is not listed on the XTAR website.

Given that the all cells are charged and run for only a minute or two, no cell will be driven into reverse polarity.

As you indicated, use only protected 18650 cells in these lights.

 

[Chippy_boy]

Thanks mate - I apprectiate you taking the time to reply.

Reading up a bit more about it, I can't see how you'd get close to reverse polarity on the smaller cell. It would have to be flat as a pancake for that to happen and it all likelihood it never goes below 2.7v in normal use. Now if you were going to run it for hours and then store it for a year or so, then yes I can see that would be very dangerous. But I really can't see how 30 minutes of run time would do any harm. The 2600 battery will be a little bit flatter (i.e. lower voltage) but since they are all in series, all that will happen is that the current through all the batteries will be slightly lower.

Having said all of the above, I won't be risking it! I just want to try the torch out to check it's working OK before the new batteries arrive in around a week.

Thanks again

 

[Norm]

Never mix cells of a different brand, age or capacity.

Norm

 

[KiwiMark]

Reading up a bit more about it, I can't see how you'd get close to reverse polarity on the smaller cell.

You just need to make sure you don't drain these batteries low enough for the lower capacity cell to go below its minimum voltage.
It should all work fine but you need to be very careful and don't run down your batteries.
As a temporary measure until your new cells arrive I think it will be fine, just realize that you need to be careful and not run the light for too long before recharging the cells.
A lack of caution here could seriously damage the lower capacity cell - be very careful.

 

[Chippy_boy]

Well you've got me all worried now. I am concerned that my existing Enerdan 3400's might not have the same capacities as the new ones (when they arrive), bearing mind they are a few months older.

So to be ultra safe, I have ordered 4 of the Enerdans. At least if they are all brand new, of the same make and capacity, I should have least worries of any horrible accidents.

 

[ven]

Well you've got me all worried now. I am concerned that my existing Enerdan 3400's might not have the same capacities as the new ones (when they arrive), bearing mind they are a few months older.

So to be ultra safe, I have ordered 4 of the Enerdans. At least if they are all brand new, of the same make and capacity, I should have least worries of any horrible accidents.

:thumbsup:
better to be safe than sorry,if in doubt dont!