Best battery chemistry for 6 weeks off grid

[andrewnewman]

Greetings:

I may spend 6 weeks this spring at a friends camp in the Great White North. There is no electricity at the camp but I suspect a flashlight (or two or three) might be useful

Given that I have a choice of lights as well as the luxury to plan ahead (it being February), I am soliciting advice on the best battery form factor and chemistry.

My current thinking is to just order some CR123 lithium primaries. I don't really want to use my Li-Ion batteries because I would end up holding a large number of them in a mostly-discharged state for weeks which just seems cruel to them. AA form factor lithium primaries are more expensive (and generally hard to come by in bulk) than CR123 primaries. AA alkalines would be the least expensive but I'd need need to carry more of them. NiMH AAs are a thought but I suspect I (or others) would run them until they were *completely flat*. Again...cruel to the batteries.

Thoughts?

 

[Kestrel]

What about some Rayovac 4.0 AA NiMH LSD's, they are pretty inexpensive online - less inexpensive than Eneloops which I wouldn't want to abuse unnecessarily. You would need more of them than the CR123's that you are considering, but at least they are somewhat cost-competitive to single-use CR123's. Even if they end up providing (a somewhat-shortened lifetime of) ~3 years of service instead of ~4 (just for example, I'm just naming a figure here for the sake of the argument), it's still much better bang-for-the-buck than disposable CR123's?

I know that cold temps might be a factor, unsure of how well LSD NiMH will perform in that situation? :shrug:

BTW definitely do the trip, it sounds like a great experience.

I think I'd just take my normal-use lights (LiIons, keeping them warm in the pockets, with CR123 cells as backups for the coldest conditions), I have found that unless I am doing much night hiking, overall use is not extensive, and your cells will last an extremely long time at the low output levels that are the most handy.

 

[Magic Matt]

I always found that a 16-hour slow charger and NiMH AAs worked pretty well when we used to go camping (well, luxury camping really as iut was a family holiday in a fancy tent, but no electric hookup). This was over 10 years ago mind! I just used to leave a solar panel on the washing line - it was a 2 watt one for emergency charging the car battery, but I had a slow charger that plugged into a car cigarette lighter, and the two linked together worked pretty well. I kept one set in my light (2xAA), and 4xAA in the charger. I put them in the charger when I got up, took them out when it got to late afternoon, as I had no idea what might happen if the light level wasn't enough to generate any voltage - the panel was probably protected against reverse current but I wasn't sure about the charger.

In terms of portability though, I think I'd forget the charger/panel because of their size/weight if you're going backpacking, and just take lithium primaries in a sturdy case so they're well protected. Forget alkalines really... LSD NiMH last longer so are more sensible. If you run them flat and abuse them, don't worry about it - it's not like you're going to makea regular thing of it, and I'm sure the loss of a few cells will be completely insignificant compared to the experience you'll get doing the trip.

 

[SFG2Lman]

if you are going to be out in the "bush" i would do the CR123 thing and have a couple lights that do the "15 days at .005 lumen level" or whatever they are rated at, with no ambient lighting those low lows are actually very sufficient. at that rate you would only need like 3 CR123s and a quark123 for the whole trip! not that thats how us flashies do it though.

From all my camping experiences a bright area lantern is worth is weight too, whether you want to go with coleman gas, fluorescent, or LED. If you go LED you'd be best off building your own as i don't think lanterns have caught up with the newest LEDs. One of those fluorescent 8 "D" cell battery lanterns is heavy, prolly need 3-4 sets of extra batteries too. But if you aren't hiking, weight isn't really an issue.

Also, if you are staying stationary you may want to modify some of those decorative lawn lights (solar powered wal-mart decorations) just to demarcate latrine areas and such. If you want to go all out...

 

[gswitter]

If you're going to be off the grid for that long, I'd bring a BoGoLight SN-2. It's not especially bright (I'd bring another light, or four), but it's usable. More importantly, it runs on (and charges) NiMH AA's. I doubt it can completely charge a set of Eneloops in a day, but you probably won't run the cells completely down each night either. Anyway, it's not too big, it's very light weight, it's puts out a usable amount of light, and it has an integrated solar charger.

 

[45/70]

With my own experience in Northern Ontario, and having quite a bit of experience living in "bush" camps, although never in February , your only options are lithium primaries. I'm talking about temps in the -40 range. At these temperatures alkaline's would be useless, and NiMH's as well. Of course, if you never go outside, which IMHO isn't such a bad idea :naughty:, and you only use your lights indoors, that's a differnt story.

Edit: I forgot to mention, at these temperatures, Li-ion cells would more than likely be damaged. The lattice structure in LiCo Li-Ions cells anyway, can be damaged at temperatures below about 0F/-18C.

Dave

 

[spencer]

Do you mind me asking where exactly you are going?

 

[Warp]

With my own experience in Northern Ontario, and having quite a bit of experience living in "bush" camps, although never in February , your only options are lithium primaries. I'm talking about temps in the -40 range. At these temperatures alkaline's would be useless, and NiMH's as well. Of course, if you never go outside, which IMHO isn't such a bad idea :naughty:, and you only use your lights indoors, that's a differnt story.

Edit: I forgot to mention, at these temperatures, Li-ion cells would more than likely be damaged. The lattice structure in LiCo Li-Ions cells anyway, can be damaged at temperatures below about 0F/-18C.

Dave

He isn't doing this in Feb. He is doing it this spring and said that since it is currently Feb he has time to plan ahead.




I would just bring an adequate supply of primary 123s, but that is basically how I do it anyway. Primary lithium something or other, though, due to runtime, output, lower temperature sensitivity and weight.

 

[carrot]

Since you are already comfortable with CR123 I suggest you stick with that. They are still the best power source you can have for a flashlight. The AA form factor has come a long way but the CR123 stores more power and is capable of powering more powerful lights.

 

[45/70]

He isn't doing this in Feb. He is doing it this spring and said that since it is currently Feb he has time to plan ahead.

Ahh, missed that! :candle: I'm glad somebody's paying attention!

Dave

 

[andrewnewman]

Right. I'm going in the spring. I'm getting a bit old for a 6 week *winter* trip in Canada! For the record, the camp is on of the French River outside of North Bay Ontario.

 

[flatline]

If you want a dim, run-forever light, consider putting a 14505 primary cell in a Quark AA or LF5XT.

The 14505 is a lithium primary with a whopping 2.4Ah capacity in a AA form factor, but can only give a constant current of about 100mA. What this means in a Quark AA is that the only mode you can use is moonmode, but if my calculations are correct, you're looking at something like 3+ months of continual output (2000+ hours of runtime).

For those who want to check my math, the QAA moonmode reportedly lasts 30+ days on a 750mAh 14500 li-ion, the 14505 is the same nominal voltage but 3.2 times the capacity, so 30+ * 3(ish) = 90+ days.

Even if I'm off by a factor 2 (or 4 if you turn it off during the day), that would be at least one flashlight that you could use 100% of the time for all six weeks (at a low level only useful at night or up close) without ever worrying about the battery.

Just food for thought.

--flatline

 

[Linger]

Use quality AW lithium cells. Try to keep levels above the low discharge cut-off. When the trip is over you have a cell that has sat at 3.5v for 5 weeks and will give you years more use. Even if the AW only gives you another year of use, way better investment then single-use primary cells.

As long as your with experienced people you'll be shocked how little you use your lights. Only needlights for cooking and washing, everything else can be done by touch / with ambient light. I've done huge paddle / portage trips with only a Petzl Tikka (3aaa powered 3x 5mm emiters) and didn't touch the spare batteries.

 

[Gryffin]

The 14505 is a lithium primary with a whopping 2.4Ah capacity in a AA form factor, but can only give a constant current of about 100mA. What this means in a Quark AA is that the only mode you can use is moonmode, but if my calculations are correct, you're looking at something like 3+ months of continual output (2000+ hours of runtime)

Your ideas are intriguing to me and I wish to subscribe to your newsletter.

Seriously… These cells are very interesting for emergency use, but the Search function's not giving me much. Got any links where I might be, er, enLIGHTened? :candle:

 

[BentHeadTX]

Are you going to be flown into the camp?

If you drive in, Maha chargers are available that can be used with 12V automotive power. My C9000 would go with me along with the 12V lighter plug in and there would be an Eneloop party going on. I would take an 8-pack of E2 lithium AA cells as a backup though. Never know when a long cold snap will hit.

 

[Nubo]

Assuming a stationary camp, with weight not being an issue and a 6-week stay, how about a good supply of the rechargeables of your choice, and to charge them, bring a fully-charged car battery, inverter and charger(s). Should be more than enough power for any reasonable battery-powered lighting needs and your "power station" could be useful for other things, such as cellphones, or even a bit of entertainment (ipod, etc). Mixing margaritas might run it down before 6 weeks....

 

[T0RN4D0]

Hehe when your camping for 6 weeks with no power supply, you don't want to have a bunch of high power battery munchers on you. You will see that your eyes adjust to dark and if moonlight is not enough, any low power LED light will do, and you probably only need to bring a few pair of AAs, alkalines or nimhs.


Not saying that having a nice bright torch isn't useful from time to time, but make sure to pick a light that has a useful low setting that lasts for a while. Once you have that, battery chemistry isn't that important, but primary lithiums are probably best if you have weight limitations. A solar charger might also be a good choice combined with some li-ions you can just top off during the day

 

[Gryffin]

As long as your with experienced people you'll be shocked how little you use your lights. Only needlights for cooking and washing, everything else can be done by touch / with ambient light.

Linger is right. If you're a city boy, you probably don't realize just how well your eyes can adapt to the dark.

Just fer grins, I've actually read a book my the light of a full moon. As a flashaholic, it's probably hard to believe, but just one single lumen of light is plenty for most camp chores.

Once your eyes are adapted, it's amazing how much you can see by moonlight alone. Try it. It's a very primal thrill, and highly recommended. :rock:

 

[MarkW]

Thought from Alaska: Haven't checked the latitude of your destination, but remember that up here in the great white, there is an abundance of daylight and not a whole lot of darkness by May. On most camping trips I am more worried about eye-shades (for sleeping) than flashlights, and summer trips require no flashlights at all. Depending on when you go, and and how far north, you may use a light less than you expect.

 

[DaveTheDude]

For off-the-grid power in portable form, check out the batteries offered by the folks at Tadiran. They offer some of the most powerful, longest lasting cells available. The link is:

http://www.tadiranbat.com/

After reviewing what's on offer, the customer service folks at Tadiran can advise you where to purchase individual or bulk cells.

Caveat: Double check your input voltages...you don't want to have theses cells vaporize your lights.