18650 Battery Strangeness

[spoolin01]

Wow, I'm all over this thing ! Seems like a great deal. Can it do "discharge" cycles ??

You can also check out the Opus BT-C3100/3400 offerings. They charge and discharge at a higher amperage, show all four channels in the display at once, and the interface is similar to that of the LaCrosse NiMh charger/analyzers, if you're used to those. There are some other differences as well, whether they justify the higher price is up to you.

The 7.5 hours was on full power.

This mystifies me. How can a high output light go for 7.5 hours on an 18650 battery, unless there's some serious winding down of drain and therefore output? Doesn't make sense to me, but it seems to be a common claim.

 

[jimbeeler]

The 7.5 hours was on full power.

The digital charger is a good idea. Amazon won't ship to Thailand without imposing huge and ridiculous customs fees, so I'll look for a different source.

Thanks to all.

I'm pretty sure I got mine on eBay so there are other sources for those smart chargers.

Jim

 

[Buadhai]

This mystifies me. How can a high output light go for 7.5 hours on an 18650 battery, unless there's some serious winding down of drain and therefore output? Doesn't make sense to me, but it seems to be a common claim.

Me, too. My real world experience has been quite different. I normally swap in freshly charged batteries every other dive, just to be on the safe side.

When I set up this experiment I was prepared for it to go on for two hours, three max. I was astounded that the light seemed to be bright as ever, six hours later. I finally just switched off the light because I was tired of monitoring it.

Plus, the light never emitted the low battery rapid flash. However, when I turned the light off and back on again, it immediately did the flash, but the light was still strong.

 

[spoolin01]

I'm pretty sure I got mine on eBay so there are other sources for those smart chargers.

Jim

Good point, most of the cheapest eBay sellers are in China and Hong Kong.

 

[Hatul]

XTAR makes nice chargers. As far as the puzzling battery goes, these are so cheap I would just throw it out.

 

[Kharon]

Just wondering - is this one of the batteries with the over/under charge protection circuit?

 

[Buadhai]

I ended up ordering a Nitecore D2 Digicharger. It arrived today. According to the scratch-off code, it is genuine….



Thanks again for all the suggestions and information.

 

[Buadhai]

Just wondering - is this one of the batteries with the over/under charge protection circuit?

Yes, it is.

 

[Buadhai]

I know everyone's bored to death with this topic, but one more thing...

I finally got the chance to put the weird-but-brand-new battery in the digital charger. At first, it displays the voltage (4.1) and the display indicates that it is charging the battery. A few seconds later the display changes to indicate that there is no battery in the slot. A few minutes later the charger turns itself off.

I've also discovered that if I'm willing to ignore the dive torch's low battery warning for a minute or two, the battery works normally and the low battery warning goes away. It can be charged using the cheap charger that came with the torch, but not with the digital charger.

I wish I understood what the digital charger "knows" about the batter. Is it able to measure something other than the voltage?

 

[NAM001]

I have some that have done that also. There is something inside the battery like a fuse that blows on excesive discharge. My batteries got put on the charger in reverse polarity and I now have what you are explaining. I just tossed them and bought more. There are others I understand that do not have that safety device in them.

I received a 18650 battery with a new Archon dive light. The battery is generic but rebranded Archon with a sticker. The battery itslef has only the following: VDA 18650 2600mAh 3.7V.

The battery worked fine for a few dives, but now, no matter what light I put it in, the light indicates that the battery is dead. If I put it in a charger, the charger indicates that the battery is fully charged.

The battery measures 4.13 volts with no load.

What are the lights seeing that the charger and my voltmeter are not?

I've got a light in a bucket of water now to see how long the battery lasts.