Backup light recommendations

[rddvet]

I'm in need of some new backup lights. I started with Intovas many years ago and realized push button sucks. Moved to some Dorcy brand lights from piranha gear that Kelly recommended and loved them for many years. One of them recently died due to a leaky battery. I ordered a LM 3watt, but I found it too bulky (I will put on harness or in pockets depending on sm vs bm). I ended up getting a halcyon 2W. It's the ideal size for me personally. After getting the new light I went to do regular battery maintenance on my other backup lights and now 2 more are dead (emmitters seem to be dying because they'll turn on but its very dim and not the batteries). Eventhough I like the halcyon, they're $200 each and I really don't want to spend $600 on backup lights.
So I'm looking for suggestions. What I want:
-nonrechargeable batteries (its not that I don't trust rechargeables, it's that I don't trust myself to remember to charge them)
-similar size to the 2W halcyon light
-has to be twist style. I won't do buttons or slides
-not $200 since I'll be buying 3 more.

 

[tbone1004]

ooh that's going to be a tough one.

So I'll play devils advocate here. This is not like the days of NiMH or NiCad where self-discharge was high. If you are going to replace your alkalines every 6 months, the 18650's will be able to go that long or longer before there is any appreciable loss of capacity. The BMS on a single cell consumes about .01mah, so call it 2mah/week. 52 weeks=100mah or about 3% of the battery usable capacity/year. Certainly a negligible amount of consumption. Self-discharge is about 5%/month *really about 2-3 these days* so over 6mos you'll lose 35% of the battery capacity which leaves about 50% of the capacity usable, ~1700mah.
On the DGX twist that will give you about 30 minutes on high per cell if you're diligent about recharging them every 6 months, realistically about 45 minutes.

Now, here's the issue. If the lights are like the 2w Halcyons since the Light Monkeys are about $110 these days, they are only about 200 lumen, so they are like candles compared to the modern ones because the alkalines just can't discharge at the same rates as the lithium cells. That may be enough light if you're kicking but it would certainly be marginal at best on the DPV.

Main argument against alkalines is that unless you bit the lithium cells in there, if you are prone to forgetting to pull them out and check them or if they get rolled on at some point and fully discharge they'll leak...

If I were you I would reconsider going with something like the Dive Rite BX2 and try to be diligent about putting them on a cell tester once a quarter or at least every 6 months? Pop the batteries out, drop them in a Opus or similar for a test cycle so you know their capacity and call it a day. It will be far easier than trying to find something with obsolete technology.

TLDR, all the above was for everyone else's benefit and I know you two have gone through all of that. Buy @OrcaTorch 's D580 and call it a day

 

[rddvet]

ooh that's going to be a tough one.

So I'll play devils advocate here. This is not like the days of NiMH or NiCad where self-discharge was high. If you are going to replace your alkalines every 6 months, the 18650's will be able to go that long or longer before there is any appreciable loss of capacity. The BMS on a single cell consumes about .01mah, so call it 2mah/week. 52 weeks=100mah or about 3% of the battery usable capacity/year. Certainly a negligible amount of consumption. Self-discharge is about 5%/month *really about 2-3 these days* so over 6mos you'll lose 35% of the battery capacity which leaves about 50% of the capacity usable, ~1700mah.
On the DGX twist that will give you about 30 minutes on high per cell if you're diligent about recharging them every 6 months, realistically about 45 minutes.

Now, here's the issue. If the lights are like the 2w Halcyons since the Light Monkeys are about $110 these days, they are only about 200 lumen, so they are like candles compared to the modern ones because the alkalines just can't discharge at the same rates as the lithium cells. That may be enough light if you're kicking but it would certainly be marginal at best on the DPV.

Main argument against alkalines is that unless you bit the lithium cells in there, if you are prone to forgetting to pull them out and check them or if they get rolled on at some point and fully discharge they'll leak...

If I were you I would reconsider going with something like the Dive Rite BX2 and try to be diligent about putting them on a cell tester once a quarter or at least every 6 months? Pop the batteries out, drop them in a Opus or similar for a test cycle so you know their capacity and call it a day. It will be far easier than trying to find something with obsolete technology.

TLDR, all the above was for everyone else's benefit and I know you two have gone through all of that. Buy @OrcaTorch 's D580 and call it a day

All good info. I'm actually reconsidering and am going to go to rechargeable I think. I was under the assumption I was going to need to charge every time I go to dive assuming they would be discharging. But it sounds like if they're not used they don't really discharge significantly so throwing them on the charger every 3 months would work.
I was considering the the dgx 600 twist on. How would the orcatorch compare? I know a few people have said orcatorches are a little bulky.

 

[tbone1004]

All good info. I'm actually reconsidering and am going to go to rechargeable I think. I was under the assumption I was going to need to charge every time I go to dive assuming they would be discharging. But it sounds like if they're not used they don't really discharge significantly so throwing them on the charger every 3 months would work.
I was considering the the dgx 600 twist on. How would the orcatorch compare? I know a few people have said orcatorches are a little bulky.

They're all about similar. With the DGX warranty it's kind of hard to look at anything else though the Dive Rite BX2's are pretty slick.
Incidentally the 18650's are actually going to be slimmer than the alkaline equivalents because the batteries are smaller in diameter.

Once every few months is not that bad though I would make sure you have something like the Opus that gives you a test function. When you pull the backup lights out, run them through a test cycle which fully charges, then fully discharges, and fully charges again so then you know their resistance *health*, and their actual capacity so you can tell when they start dying.

 

[grantctobin]

Seconded. Have a couple LM 2W, a couple of the Edd blue ones that I’ve broken, the old Intovas, etc. Waiting on a pair of BX2 just to be done with it. The CX2 are tempting, but too large for what they are. Brings everything down to a primary, an LX20+ as backup primary, and 2 BX2.

 

[wKkaY]

So I'm looking for suggestions. What I want:
-nonrechargeable batteries (its not that I don't trust rechargeables, it's that I don't trust myself to remember to charge them)
-similar size to the 2W halcyon light
-has to be twist style. I won't do buttons or slides
-not $200 since I'll be buying 3 more.

I went shopping for backup lights recently with more or less the same criteria as you and ended up with two of the LM 2W.

When batteries are fresh they seem bright enough, but I'm not sure whether they'll be unusably dim as they deplete.

 

[kensuf]

Just make sure they don't have buttons that can easily turn on if bumped. The two people I dove with last Sunday had backup lights turn on a total of 5 times on one dive.

 

[rddvet]

Just make sure they don't have buttons that can easily turn on if bumped. The two people I dove with last Sunday had backup lights turn on a total of 5 times on one dive.

Learned that lesson years ago

 

[Manatee Diver]

Just make sure they don't have buttons that can easily turn on if bumped. The two people I dove with last Sunday had backup lights turn on a total of 5 times on one dive.

Part of the reason why I loved the CX1. I am too much of a shaved ape to handle twist ons. Buttons work better for me, and the tail button rarely gets bumped on.

 

[Marie13]

Part of the reason why I loved the CX1. I am too much of a shaved ape to handle twist ons. Buttons work better for me, and the tail button rarely gets bumped on.

Yep. I much preferred the CX1. Lost one when my SM rig was stolen last fall at the local quarry. I keep my backup lights on my shoulders and the CX2 are just too big. Have to be careful how I put them on my shoulders to not trigger the button. I don’t like twist on lights.