Manker 14500 battery overheats and leak (in Manker E11)

Hi BLF!

Today I absently inserted a (Manker) 14500 battery in inverted position in my Manker E11: “+” to towards the tail cap and “-” towards the driver. After some minutes I touched the flashlight and it was astonishingly hot, almost unbearable to touch or grab.
Nonetheless, I managed to remove the tail cap and to take the battery out. To cool it down I put it outside the window as I also didn’t know if it could explode. The plastic outside the battery melt a bit with the heat… (Imgur: The magic of the Internet / Imgur: The magic of the Internet )

After some minutes I went to see it and it was cooler, but I felt a strange smell on it. It was leaking on the top so I left it outside so the toxic smell didn’t stay inside the house. (hard to see but this is where it leaked Imgur: The magic of the Internet )

With this situation I learned that the Manker E11 has NO reverse polarity protection. :open_mouth:
In the flashlight manual it says “Note: pls put the anode (+) towards flashlight head, flashlight won’t work once battery reverse” (http://imgur.com/pUQcLKr).
However, it never says something like“Caution: No reverse polarity protection; risk of overheating and/or exploding”!

I would never blame Manker for my mistake, but a warning should have been made in the manual, I would have been more careful. People are at risk with this kind of “unprotection”!! Especially being a stock light, that is made to be used with Li-ion batteries.
So, my advice for Manker (or any manufacturer…), please make your lights with reverse polarity protection or, at least, mention it on the manual.
And…I’ve also noticed that it doesn’t have Low Voltage Protection… Oh well… :person_facepalming:

I also learned that Li-ion batteries are not a toy. Still, I’ll continue to use them, as this was my first episode bad with this type of battery, I am normally careful with them, and also because my lights need them as well.

Still, I have 3 questions, bearing in mind this episode:

  1. Do Li-ion protected batteries avoid this kind of overheating (and/or explosion) when we put them in inverted position in lights that don’t have that reverse polarity protection?

2) Although the Manker E11 can’t be used with protected 14500 batteries… :person_facepalming: … can you recommend me, please,
a) good protected 14500 batteries
b) good unprotected batteries?

3) Do Ni-MH batteries avoid this kind of overheating (and/or explosion) when we put them in inverted position in lights that don’t have that reverse polarity protection?

Thanks in advance for your answers! :+1:

I love the Manker E11, it is my most used light, but those who own it, please don’t get distracted when inserting the battery !!

Best regards!!

I honestly don’t think that a notice in the manual would have prevented this (who reads those things anyway), but yeah reverse pol. protection should be standard in li-ion lights I guess. I wonder if this would happen to any cell in any light without polarity protection?

In my skilhunt H15 I use a protected keeppower 14500 800mAh. The H15 has mechanical reverse polarity protection so it can only be used with button tops.
For my klarus I use unprotected Sanyo UR14500P (flattop cells).
I’m happy with them but they are not for high drain applications but I prefer runtime over max output anyway.

Check HKJ tests to find out which are good batteries.

Hi dekozn!
Thanks for you comments and suggestions!
Perhaps the information on the manual - for guys like me that normally read them not to mess things up :smiley: - could be at least a warning! But the protection would be better, though!!

But yes, I messed up, and that’s a fact :person_facepalming:

+1 Good question! The other lights I have, have polarity protection, so the light doesn’t work, but doesn’t heat up, too! Can’t really answer this question…

Yup, these are the ones I’ve seen more referred! Nice to know the Sanyo has good runtime, I thought it would be a “sprinter”, not a “marathonist”.
I’ll compare these two on HKJ tester, if represented there.

Do you know if there are also any unprotected 14500 Keeppower? I have some 18350 from Keeppower and I’m happy with those as well, they seem reliable so far, but I guess I never found unprotected 14500 from them…

Thanks once again!! :+1:

Why would the battery leak if reversed? I know that feeding voltage in the wrong polarity can destroy the led and possibly the driver, but I didn’t know it could damage the cell. The only cause I can think of is that reversing the cell somehow caused a short-circuit inside the flashlight.

Hey ggf31416!

Sorry, I may have explained myself badly ! I guess it’s time to go to sleep :person_facepalming:

The battery leaked after taking it out, outside the flashlight, not inside!
It was soooo hot when I took it out, that it may have provoked some internal damage on the top…
I can’t really answer about the physical or chemical reasons that led to that.
I just know that it did leaked a bit of liquid and strange not pleasant smell.

keeppower does not make batteries so buying unprotected from them is a waste of money. you are paying for a wrapper on a chinese battery. for unprotected buy sanyo or efest

it sounds like the cell was damaged from a direct short

Not really no never looked in to them, I think the keeppower is just a rebranded sanyo or somehing with a protection board added.

@ pirate joe 22
Hum, didn’t know that! Maybe I’ll seek for some Sanyo then!
Thanks!! :+1:

@ dekozn
Same as above :smiley: I’ll look for some Sanyo like those you mentioned. Don’t really know if Nkon has them, but I’ll search it!
Thank you! :+1:

My question, however, remain:
Would Li-ion protected batteries avoid this kind of extreme overheating or without the flaslight polarity protection any battery would be at risk?

Concerning the Ni-MH I tested my Panasonic Evolta in inverted position just to check and they got hot after a few seconds, although maybe a bit less than a Li-ion due to inner voltage.

I think that Manker needs to weigh in on this and explain why the light doesn’t have reverse polarity protection :question:

I got mine from banggood, I find em kinda expensive compared to the energy you get from 18650 cells. I just wanted some to test my FL.
As for the other question I can’t really answer that. If the heating is caused by a short it should trip the protection, I don’t know if the pcb has a temp. sensor to trip the protection when overheating but I doubt it.

@ djburkes
Hum, I wrote about this experience to alert the users and, eventually, manufacturers about the risks of using and making flashlights with no protection.
Maybe Manker can say something about this, and eventually change their specs in the future. Them and other companies!

For users, we always have to keep an eye on what we do with the lights and batteries, as they may turn into real “pocket rockets” and not in a good way… :zipper_mouth_face:

@ dekozn
I may order mine from Gearbest or AliExpress, as I want to use the Manker E11 with full power! They’re sold out in Banggood and Nkon. The prices don’t vary a lot among these stores, though.
Concerning the question, maybe you’re right, maybe even protected batteries don’t have a temperature sensor, so the flashlights should have them…

Thanks! :+1:

Very good to know, and it is very careless of Manker not to have reverse polarity protection in a flashlight intended for li-ion use. The very simple and budget NANJG drivers, even back in 2011, already had reverse polarity protection, it should not be such a big deal building it in, especially for Manker who does their own driver design.

Related to this, I have two Utorch UT01 flashlights on order which are pretty identical Manker E11 clones. I take it that it will have the same flaw? :frowning:

Hum, I am not familiarized with those drivers, but I guess that other cheap lights I have - even those that use Li-ion batteries - have that protection or, at least, they don’t get hot or anything like this one did.
And the Manker E11 is not a cheap light, at least in my point of view!

I also thought about that, maybe the Utorch UT01 has the same problem.
They seem to be clones, with some small differences, so maybe UT01 has the same issue. Hope that you and other owners don’t get any trouble with them.
Please, let us know if this happens when you receive yours.

Maybe BLF can start a sensitization close to manufacturers so that they could use polarity protection in all stock lights, in order to avoid these situations.
Safety over lumens… :wink:

I don’t think a temp sensor in the light will help for protecting the battery, specifically in this case where the battery is put in the light reversed. Temp sensor in the light are for protecting the LED and driver.

Ehhh, oops :smiley:
I thought it would be integrated in polarity protection, preventing from getting hotter, not the LED, but the battery. I was wrong :person_facepalming:

Still, one of my concerns yesterday was the LED functioning (the head of the light also got hooot), but it works fine. I’m using the E11 with Ni-MH battery, and it works fine.

I don’t know if the electronic components suffered any damage, but so far the light is working normally. :+1:

Would you be able to dismantle the light and take photos of the driver board and other circuit details to determine what was the current path for the short circuit? It might be that current was flowing thu the body diode of a FET, but it would seem that the switch would block current (or was the switch ON with the reversed cell?)

Hum…I’m afraid I can’t do that. The light is not so friendly (for me) to take the parts out and then put them back together without really damaging it !
I looked to the driver’s bottom and everything seems fine. The interior, I don’t know, but dismantling it…I may ruin the light.

However, I can assure that the switch button was OFF yesterday, as it was some hours ago when I tested the inversion with the Ni-MH cell! It also got hot, but just a bit as I took it out after testing.

So, there seems to be a continuous “current” through the light when it is inverted, even if the switch is OFF.

If i understand correctly the battery shorted just by being inserted the wrong way! That’s quite a disturbing and dangerous design flaw!

Reverse polarity protection is intended to protect the light (driver and led) and can be implemented both mechanically and electronically. In your case not only there is no such protection, but even worse, it will actually create a short.

A protected cell should prevent that… if you can insert it in the light - lol.

While I agree that putting in a diode, or a plastic stand off for reverse polarity isn’t a big deal an probably should be done it’s not Mankers fault that the OP put the battery in backwards. It is the OP’s responsibility to insert batteries correctly and he is responsible for what happened.

Bob

To say it more precise because it is an electronic switch, it is not the switch that is off, but the MCU is in off-state. So the driver is always in contact with both sides of the batteries, there’s no physical circuit switch-off.