Confused... Batteries shorting out for no reason? Host issue...

Trendkilla254 said:

Based on the picture, if the positive end of the battery is going toward the front of the laser, it would short out the battery. That little solder "tail" is long enough to make contact to the center post positive and the case of the battery (the negative). I would normally suggest to get a small little neodymium battery and stick it to the positive end of the battery and insert it, but you already have the issue of the host being to tight.

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How? The battery is supposed to circuit negative through the host, apologies I can't quite understand what youre saying.

As for Isaac and Paul, the solder connection is functional and does power the laser. It only shorts the battery when it's tightened, or so I think. Also, when I manually connect the end of the battery to the host, it works fine.

Also remember, the tailcap's only purpose is to complete the circuit through the host. Imagine the tailcap and the solder blob is just one piece, as it all conducts the same polarity - negative.

Not sure why but I find this oddly confusing, am I not understanding something?

i asked for the battery brand.....

what i'm trying to do is find all the variables and begins the process of elimination...
-picture of battery.
-picture of the front end.
-picture of how you soldered the module to the host.

it may seem long and endless but as a saying go
-'the closer you look, the less you see'.
-'what might go wrong,will go wrong'.
-the easiest way to find the solution is to come up with all the possible answer and begins the process of elimination, the last remaining solution is the right one....'

Isaac Clarke said:

i asked for the battery brand.....

what i'm trying to do is find all the variables and begins the process of elimination...
-picture of battery.
-picture of the front end.
-picture of how you soldered the module to the host.

it may seem long and endless but as a saying go
-'the closer you look, the less you see'.
-'what might go wrong,will go wrong'.
-the easiest way to find the solution is to come up with all the possible answer and begins the process of elimination, the last remaining solution is the right one....'

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- batteries have been shorted out to .1 volts and thrown away at electronics recycling
- front end of ??? the host? focus ring
- I just soldered the module to the + and - terminals that ehgemus provided me, as this is a pre-built host. Just two wires in heat shrink tubing, nothing special honestly.

Your quotes are very true

edit: I used two trustfires, two no names and I can't remember the other set. All dead from the constant shorting...

I believe the top picture is the tail cap. That is the negative battery contact. If this is the case, how can it short out the battery? He said that the batteries go in positive first and he can't show that part of the laser. Now, there is a contact board inside the front end for the positive battery connection. It is possible that there maybe a short there that is sensitive to the pressure on it.

...... try a pair of quality battery and report back.. i'm talking AW here....

no name and fire battery are rewrap old battery on the verge of dying.... that explains the whole situation........(those thing short themself, and many others thing...)

paul1598419 said:

I believe the top picture is the tail cap. That is the negative battery contact. If this is the case, how can it short out the battery? He said that the batteries go in positive first and he can't show that part of the laser. Now, there is a contact board inside the front end for the positive battery connection. It is possible that there maybe a short there that is sensitive to the pressure on it.

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This!!! This is basically what I'm asking in this thread, it makes no sense why it's shorting out.

The pressure could indeed be a possibility. Unfortunately I have no way of finding out whether that's the case internally, the top part does not budge.

Isaac Clarke said:

...... try a pair of quality battery and report back.. i'm talking AW here....

no name and fire battery are rewrap old battery on the verge of dying.... that explains the whole situation........(those thing short themself, and many others thing...)

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Understandable but I had them anyway, and seemed to work fine. If it's just the battery, then why would the exact same thing happen every time? I used the batteries in other lasers before, and they were good working batteries, 4.1-4.2v, before they shorted.

If I'm right, the only difference that quality batteries would have would be that they would protect themselves and lock out during the short circuit.

ElectricPlasma, I believe you have a short in the contact board from everything you've said here. I think it is pressure sensitive and is causing the problems you have described. Putting more batteries into it maybe a sure way to destroy two more batteries.

picture not working.....

the fire brand and no name have alot less capacity and can't stand high current draw.... most of them fail if the draw go over 1amp.

Isaac Clarke said:

picture not working.....

the fire brand and no name have alot less capacity and can't stand high current draw.... most of them fail if the draw go over 1amp.

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That's what I'm saying, they didn't fail, they shorted. I can tell because they heated up when the laser was not active.

paul1598419 said:

ElectricPlasma, I believe you have a short in the contact board from everything you've said here. I think it is pressure sensitive and is causing the problems you have described. Putting more batteries into it maybe a sure way to destroy two more batteries.

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Thanks Paul. I believe this is the issue. I picked up some CR123A's that are a bit smaller than 18350s, just to try out as they were quite cheap. I tried them out. I screwed on the tail cap all the way, it was a tad short. Put a small spring in there between the tail cap and the battery closest to it, screwed it in all the way again, worked flawlessly. I think I'm just going to melt the solder blob to the spring, and use some rechargeable CR123A's.

Thanks again.

All the clues point to the front battery is shorting due to how that positive connection sticks out. It appears to me there it is not just a nub but theres a piece jutting out to the side. When you add too much pressure you are getting a direct short on the front cell and that is why you noticed it getting very hot and not the back cell so much. Because they are connected though the rear one is trying to take up the load of mismatched cells and that one ends up blowing too.
I would like to see closer up picks down the tube to see what exactly that positive connection looks like. Even though the end cap looks pretty crappy it is not the issue.
Now there could be some other problem with a pinched wire or something with that side switch you might have to send it back to have him take it apart. Looks like you still have to send it back anyways for him to fix due to the problem I stated.
Are you using flat nose batteries or ones with the nipple? My guess is the flat ones as you would have to flatten the nipple ones to short unless something was sticking out on the positive connection. You could likely get rid of the issue by soldering a nipple on the end of the positive of the front cell. You could use a small magnet but I wouldn't on the positive end as it could move out of place and still short.
You have been lucky if they direct shorted. Lithium cells are not something you want to short out. My guess is that unit takes 2 batteries either 18350 or 16340 and the extra length of the 18350 is what is making it easier to cause the short because of how hard it pushes against the positive.

Didn't know someone else was answering while I was. That unit should work with the correct cells. There's no way you should have to use 16340 cells if it is advertised that 18350 will work. If those cells have a flat top that is the likely reason for them beiing too short. Button tops will add length. You shouldn't have this problem. IM assuming the positive point inside the tube moves to accommodate cells. Something is wrong with it. Or whatever it is connected to is being pushed with it and shorting. I still don't like that it can happen and if nothing else take those batteries out everytime after use and keep an eye on it during use. I would feel really edgy about it.

Pman said:

All the clues point to the front battery is shorting due to how that positive connection sticks out. It appears to me there it is not just a nub but theres a piece jutting out to the side. When you add too much pressure you are getting a direct short on the front cell and that is why you noticed it getting very hot and not the back cell so much. Because they are connected though the rear one is trying to take up the load of mismatched cells and that one ends up blowing too.
I would like to see closer up picks down the tube to see what exactly that positive connection looks like. Even though the end cap looks pretty crappy it is not the issue.
Now there could be some other problem with a pinched wire or something with that side switch you might have to send it back to have him take it apart. Looks like you still have to send it back anyways for him to fix due to the problem I stated.
Are you using flat nose batteries or ones with the nipple? My guess is the flat ones as you would have to flatten the nipple ones to short unless something was sticking out on the positive connection. You could likely get rid of the issue by soldering a nipple on the end of the positive of the front cell. You could use a small magnet but I wouldn't on the positive end as it could move out of place and still short.
You have been lucky if they direct shorted. Lithium cells are not something you want to short out. My guess is that unit takes 2 batteries either 18350 or 16340 and the extra length of the 18350 is what is making it easier to cause the short because of how hard it pushes against the positive.

Didn't know someone else was answering while I was. That unit should work with the correct cells. There's no way you should have to use CR2 cells.

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Thanks for the reply Pman, I appreciate it.

CR2's are actually a quite a bit smaller than CR123A's. CR123A's are very close to 16350s, only a tad bit smaller. I was using the nippled batteries, but I think the large batteries + the solder was all too much pressure for the contact board. Also, that nub thing jutting out to the side is the contact board if that's what you're referring to, that sends the battery connection to the circuitry.

It's not just the first battery that shorted out, both batteries died in the long run when unattended. The battery closest to the diode just got hot first. Lucky for me, there was no venting. Only severe action that occurred was the heat. Melted the battery branding.

The host was made by Ehgemus. I would contact him for help, but he has told me he's taking a break. Besides, I would much rather use simple rechargeable CR123A's for the thing rather than go through the hassle of sending it and have him to something to repair it, rebuild the module back into it, etc.

Here's what I put together for the tail cap for using the smaller CR123A's:



All together everything works. I can tighten the tail cap as much as it goes and everything's still in operation, no errors. Love it! I tried to clean up the solder and try to make it more neat when putting in the spring, besides the oxidation from the soldering iron which I have to clean off I think it's done for now.

And here's a wide angle beam shot of the laser for good riddance:

Ok I realized that by saying "tail" I wasn't clear. The positive contact board, not the tail cap. If you look at the picture of the inside of the tube you can see a very ugly solder blob. On the right hand side is a "tail" solder blob. On the positive side of a battery you have a roll over lip that seals the case shut. This is negative. It is likely that when you are tightening the host it is putting so much pressure on the battery that the positive "cap" is crushing in and flattening to the point that that little "bridge" "tail" "solder blob" is making a complete circuit.

That was my theory anyway. Explained much better by Pman.

YES! Trend has nailed what I was saying and completely understands. I had originally wrote CR2 because that is what I mistakenly thought you said and then fixed it after re-reading what you wrote a few minutes after so if you read it again you will understand. I did explain the battery thing too. I specifically asked for a photo of that positive down the tube as that's the key to the issue here. I understand if you can't take a better closeup of it.
Any way you look at it you can see why I am still concerned as Trend mentioned. If built correctly that should not happen.
Ehg is a great guy and wonderful builder. Everyone makes mistakes and doesn't catch things. You did a nice good on the spring thing to give you some leeway. I still recommend you don't store the batteries in it just in case because of what happened.
Another thing you could do is put electrical tape around the positive nipple/button top or flat top so that only that point could touch the positive contact.
If you are saying that side piece next to the positive battery connection is the driver or contact board sticking out and you think it is tilting when you put pressure on the contact that's not good. It should not move.
Please don't take offense to my help. I've built 100's of units but don't sell them and am very good at finding solutions to build issues and troubleshooting. I'm not getting on you, just trying to keep you and your stuff safe
Anyways, read what I wrote again slower

EletricPlasma, I tried to post last night but the forum was down for some reason. I wanted to say that I hope everything works out for you, but I have a bad feeling about that short circuit and it's intermittence.

Pman said:

YES! Trend has nailed what I was saying and completely understands. I had originally wrote CR2 because that is what I mistakenly thought you said and then fixed it after re-reading what you wrote a few minutes after so if you read it again you will understand. I did explain the battery thing too. I specifically asked for a photo of that positive down the tube as that's the key to the issue here. I understand if you can't take a better closeup of it.
Any way you look at it you can see why I am still concerned as Trend mentioned. If built correctly that should not happen.
Ehg is a great guy and wonderful builder. Everyone makes mistakes and doesn't catch things. You did a nice good on the spring thing to give you some leeway. I still recommend you don't store the batteries in it just in case because of what happened.
Another thing you could do is put electrical tape around the positive nipple/button top or flat top so that only that point could touch the positive contact.
If you are saying that side piece next to the positive battery connection is the driver or contact board sticking out and you think it is tilting when you put pressure on the contact that's not good. It should not move.
Please don't take offense to my help. I've built 100's of units but don't sell them and am very good at finding solutions to build issues and troubleshooting. I'm not getting on you, just trying to keep you and your stuff safe
Anyways, read what I wrote again slower

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Haha thanks man, I take no offence whatsoever. I welcome and appreciate any and all help

Thanks for the tips, I'll actually try putting electrical tape on later!

paul1598419 said:

EletricPlasma, I tried to post last night but the forum was down for some reason. I wanted to say that I hope everything works out for you, but I have a bad feeling about that short circuit and it's intermittence.

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Thanks, I've don't have the best feeling for it either but I haven't experienced it at all since I used the CR123A's and installed the spring. Also, I don't understand what you mean by intermittence?