Looking for advice on canister batteries

[high/baric]

Greetings,

I'm not 100% sure this is the right place to ask, but couldn't really think of a better one either. I suppose the target audience of this forum have canister lights that are in heavy use. I'm about to get myself a serious canister light and am currently mapping my options. As I mostly dive in cold water, this canister battery could be used for a heating vest as well. Now, there are some used canister lights on the market, but considering the battery is by far the most expensive component in the system, I'm a little worried about the life expectancy of the battery itself. The used canister lights seem to come in two basic categories:

1. The light has hardly been used (say max 10 hours per year), battery kept at high charge and never let to completely drain.
2. The light has been used regularly (say at least 30 hours per year), battery perhaps drained fully a couple of times during use.

The available setups seem to use Li-ion batteries (for example Light Monkey). A quick search on them gives a rather grim impression; capacity decay of 10-15%/year is quoted in a couple of places, with expected shelf life of only 3 years? Surely this can't be right.

Can anyone give an estimate on how long these batteries should last, from personal experience or otherwise? Basically, how often do you need to replace the batteries in your canister light setups? I think it would be a good thing to know before investing in a setup that may need a 700-1000€ battery replacement periodically. Should I even consider a 3-5 year old used battery, even if it has only seen light use?

Thanks in advance!

 

[tbone1004]

mine is still going after over 6 years. It all depends on if the cells used are high quality and how well you take care of them. Remember, the technology is exactly the same as that in your laptop and cell phone batteries. Nothing other than Li-Ion is worth looking at and I don't know of any respectable mfg's that are still using anything else

If you're using for heated vests, you'd be wise to explore the UW Light Dude offerings.

edit: apparently Halcyon still has nickel options, but you are a bloody moron if you buy one of those lights new....

 

[KevinNM]

I have been told that light monkey got their lithium packs approved for transport on airlines (apparently as part of a big fed contract), which can be a problem with some big battery packs.

 

[divad]

edit: apparently Halcyon still has nickel options, but you are a bloody moron if you buy one of those lights new....

You left out DiveRite. Re "bloody moron"; what are you, a bloody tosser?

 

[tbone1004]

apparently dive rite. regarding bloody moron, I figured it was less offensive than what I was really thinking which would have gotten *'d out. 3 years ago, nimh was viable due to the cost of lithium, but these days you are paying the same price for less power, and that really is stupid... Dive Rite charges an extra $150 for the lithium, but you get 2x the burn time in the same canister. So yeah, you really are stupid if you buy a new nimh pack. If you're that strapped for cash, there are fantastic options out there using lithium that are better lights than the Dive Rite and Halcyon for less money to begin with.

that said, to the OP, point still stands, if you are intending to use it with a heated vest, the vest controller on the UWLD offering is a true game changer since it turns the vest from "on/off" control to stepped heat control.

 

[divad]

apparently dive rite. regarding bloody moron, I figured it was less offensive than f*cking idiot.... same price, less power, less stable, and shorter life. yeah, you're an idiot if you buy a new light with nimh batteries...

Really, what do you think of someone who retreats from lithium ion back to nimh batteries?

 

[tbone1004]

Really, what do you think of someone who retreats from lithium ion back to nimh batteries?

why would you? 2x the burn time for the same size package for basically the same cost... doesn't make sense to use nimh anymore

 

[divad]

why would you? 2x the burn time for the same size package for basically the same cost... doesn't make sense to use nimh anymore

They're cheaper, safer, have more than half the burn time and aren't in danger of being banned (or confiscated) on airlines.

 

[tbone1004]

they're not significantly cheaper, the cost/wh is roughly the same for the actual packs. The fact that mfg's sell them cheaper is because they are putting half the wh in the same size battery pack. NiMH is ~90% the cost of lithium/wh, but 50% the energy density. So yes, you spend half as much on the pack, but get half the burn time. The Dive Rite light has 3.5hrs burn time, if I was OK with 3.5hrs burn time, I wouldn't have a canister in the first place since the lithium energy density has grown to the point that the handhelds can keep up with the LX25-NiMH both in brightness and burn time.

If you use a high quality properly protected pack, the packs aren't significantly safer. If you were concerned about that you would replace your laptop, cell phone, etc batteries with nimh.

if you buy high quality packs from reputable mfg's, they are un38.3 compliant. There is no real risk as long as the packs are certified. The UWLD cans actually have un38.3 certified machined onto the canisters for idiot proofing. The big Light Monkey packs while UN38.3 compliant are only compliant when they are disconnected which is very risky imho since you have to rely on TSA being in a good mood if they start asking questions

 

[divad]

If you use a high quality properly protected pack, the packs aren't significantly safer. If you were concerned about that you would replace your laptop, cell phone, etc batteries with nimh.

I'm not concerned with the safety of my laptop, cell phone, etc. I'm concerned with getting a large canister of batteries through the TSA without having them confiscated by a strident TSA agent with a newly printed copy of Rules that they don't fully understand.