I’m new to 18650 flashlights. So I recently purchased a T20 Infrared illuminator (single celled ultrafire torch customized with IR pill) from ebay. Being ebay and a customized torch, it didn’t come with instructions. I opened it up, saw the spring at the top near the the head and inserted the battery negative end to the spring. Nothing happened when i looked through my night vision, so I thought maybe I got a defective IR illuminator or maybe I need button tops as the batteries I purchased were flat top. After a bit of googling, found another seller for t20 ir which specified positive end should be towards the head, and most torches being positive towards the head. So I corrected the orientation and it worked fine no problems.
My question is, do you think the t20 got damaged (e.g. less illumination than normal) when i inserted the battery the wrong way around? I did it a few times trying to get it to work. Do you think the battery got damaged and is potentially dangerous? The battery I used was a sanyo ur18650fm 2600mah unprotected, I ordered the protected ones from gearbest, unfortunately they mistakenly sent me the unprotected, so I chose to get the free refund and use the unprotected.
The t20 seems to work fine, battery charges fine in the xtar vp2. Just want to check if i’m putting myself at risk by continuing to use a battery that has been inserted the wrong way. Also want to check if the t20 is no longer working at its full potential so I might decided to buy another one.
Thanks for the help, I’ve been lurking for a while. Being self centered, I only registered a account to ask this question, otherwise I will continue lurking, never registering. Couldn’t find anything definitive using search and typing in battery wrong way.
If your headlamp works, then you’re good. I have damaged a headlamp by doing this once. The spark SG3. There have been other occasions where I did it, but nothing happened. The light just didn’t turn on. If he light operates normally, then I don’t see anything wrong. I think you’d know right away had you. And as far as the science about the battery… I feel like the battery should be fine, as in- it’s not the battery that’s has anything done to it if you put it in the wrong way. Again I’ve certainly had no ill effects to any of my stuff… Save for the one headlamp. Oh yeah there was a second light that didn’t have it… But the light and battery were also fine. I just remember the tiny light heating up very quickly.