Strobe and rechargeable batteries??

[JohnN]

I know this is years down the line, but I've ordered 18650 3.7V 2600mAh Li-ion batteries for my Sealife strobe. I am pretty sure that they will do me much better than the standard 1.5V AA off the shelf batteries. Is there anyone reading this that use the same spec batteries or are there other suggestions that is tried and proven.

What happens when your strobe floods? I thought Li-ion batteries did nasty things when exposed to salt water

 

[fmerkel]

Motors can take more voltage.....up to a point before they fry. Electronics CAN be designed for it and if so it likely is so indicated in the manual. I have never seen that capability for strobe.

The 3.7v for Li-on is the "nominal" voltage. If you are using a Li-on and the working voltage is dropping below 3.0v/cell then it is being abused.

If a Li-on is pulled down to 1.5v under load it is being grossly overused, or is a crap battery. Just like there are crap NiMh there are EVEN MORE crap Li-on. If a 18650 claims to be over 3600mA or is named [Ultrafire] I guarantee it is crap.

14500 is just a smaller Li-on just like a AAA is smaller than a AA. Same voltage as a 18650 though, just less (lots less) capacity. In fact a 14500 is generally ~750mA and an Eneloop is ~2000mA, so unless you NEED the higher voltage it would be a poor economy to use a 14500. I do on one of my small LED (non-diving) lights but it's clear that it does not last as long even though it is brighter. A strobe charges a capacitor to create a very brief and high voltage charge to fire the light. The light is not powered directly by the battery. Lights and strobes are not even the same thing.

 

[fmerkel]

Double post....deleted. No idea why.

 

[DandyDon]

Motors can take more voltage.....up to a point before they fry.

Yeah, we try to avoid using 24 volts. It's bad for the two batteries donating, too. This was just my only experience at over volting, and I know that' not good. I guess he was wrong about his 3.7 volt batteries only supplying 1.5 on demand. I know very little on this tho, so thanks for clarifying.

Now if we can get 10,000 mAh in a camera battery, that would be nice. 700 just sucks.

 

[dmaziuk]

Yeah, we try to avoid using 24 volts. It's bad for the two batteries donating, too. This was just my only experience at over volting, and I know that' not good. I guess he was wrong about his 3.7 volt batteries only supplying 1.5 on demand. I know very little on this tho, so thanks for clarifying.

Now if we can get 10,000 mAh in a camera battery, that would be nice. 700 just sucks.

I'm sure you can get one that says 10000mAh on the label... Otherwise I think most car batteries will deliver 10 amps for an hour, we just need to hook one up to the camera.

Back to topic: if the strobe is firing off capacitors and the battery is only charging the caps, then the issue is caps' rated voltage & quality in general, and whether there's overvoltage protection circuit. At the price u/w strobes are sold for, they better have plenty of both.

 

[fmerkel]

Flooding batteries:
It's bad for all batteries, worse for good NiMh, and even worse for good Li-on. It's a direct correlation with how bad the flood is, and how good the battery is at delivering current. Saltwater shorts them, electrolysis starts, contacts start dissolving, and gas builds up.
Rechargeables have lower internal resistance, which allows them to deliver current better. That's good for the electronics most of the time but very bad in a flood as the chemical-electrolysis reaction is worse.

First thing you should do is get the batteries out, and rinse the cavity with fresh water.

10,000mA batteries.....yes, that would be good but don't hold your breath. They keep making electronics smaller and something has to give, often the battery. It's easy to change out above water, not diving. Frankly one of the better ideas was the old 4xAA Canons. Good size to hold, batteries lasted a long time, plus easy and cheap to buy. Didn't fit in your pocket though.

 

[DandyDon]

10,000mA batteries.....yes, that would be good but don't hold your breath. They keep making electronics smaller and something has to give, often the battery. It's easy to change out above water, not diving. Frankly one of the better ideas was the old 4xAA Canons. Good size to hold, batteries lasted a long time, plus easy and cheap to buy. Didn't fit in your pocket though.

My first Sealife DC100 used 4 AA batteries, and I was pleased when my next Sealife DC310 only used 2 AA - 5,000 mAh with good quality batteries. My current everyday Canon uses 2 AAs.