(rechargeable) Battery chemistry best suited for storage abuse

That's pretty much the opposite of what I've read.

Maybe some references are required.

I see we're mis-communicating here.

The purpose of a bug out bag, AIUI, is to skeedattle. You won't have time to charge your dead rechargables with zombies hot on your tail.

Load some alkies into your ZombieBlaster(tm), and blast away until they're dead (Zombies or alkies). If the latter, take out a few more of the former throwing the dead cells at them.

When the sun comes out the next day whip out the solar cooker. Slow-cooked Zombie stew's a treat.

Cheers, James Arthur

Exactly. I don't intend to. While it would be *nice* to have "freshly charged batteries" available, I would much rather have batteries that I

*can* charge instead of batteries that *are* charged but that will be trash, once depleted.

For example, the crank radio batteries are deader'n a doornail. But, I can wind it and have a functioning radio (for 15 minutes). Then, wind it *again* and *again* have a functioning radio. Etc. The "transistor radio" (showing my age) with alkalines in it is excess baggage as soon as those cells die.

I can (hopefully) recharge some "rechargeable" chemistry from one of the solar chargers; or, a hand-crank unit (assuming I am walking out). If shelter-in-place or drive out, I can recharge them from car (lighter socket), roof mounted PV panel (at home), etc.

What I *don't* want to have to do is ration *one* "factory charge" that I can never replace (until I can find a *store* to purchase replacements)

Absolutely second that--NiMH in series MUST NOT be let go flat in any device with non-zero drain. IIRC Duracell and Energizer both warn against it.

I was speaking of OEM boxes of bare cells, not under load.

That's the OP's application.

Bug Out Bag--a bag pre-packed with items one might need in an emergency or natural disaster.

I gave up on rechargeable alkalines. They wear out quickly, then leak.

I didn't see any contraindication on that page. Charging to lower voltages greatly improves cycles, mostly for mechanical strain reasons AFAICT.

I've heard that. I'd like to know the mechanism. I haven't rigorously tested, but I've kept LiIon's at high state-of-charge for years without noticing any degradation. The vast bulk of my stores, though, mindful of such reports, I try to store at 3.8V.

I'd think it was cost more than any other factor. Lead acid's cheap.

I recently did a charger for a 250WHr LiIon. The batteries are $500 each.

Cheers, James Arthur

Hey, how about circling back into the problem?

Flywheel. Indefinite durability, can be charged up quickly, can be discharged quickly, if mounted properly (parallel to the Earth's axis of rotation) has very small "discharge" rate. Cons are that it probably isn't portable in the charged state - unless it is vehicle mounted - and that you will probably need to make the choice between "low tech but bulky (several tons)" and "high tech, but not replaceable without a functional market".

Although - let's face it - if the market died, so would three quarters of us as well. So it may make sense to not really consider that possibility.

No wait - BS. Deep cycle liquid lead acid. Store the batteries dry (no water). Upon bugging out, add water, charge, enjoy.

Lead acid also has the advantage of being quite reasonably low tech so should weather even extensive market collapses and disturbances.

I heard this too, but the mechanism I heard was that the battery would somehow discharge through the concrete. Interstate Batteries says this was true back in the day, but now we enjoy better living through chemistry:

Matt Roberds

Actually, if you plan on using wood for burning, the trees need to be dry. It takes about 6 months to properly dry a tree trunk. If you are an expert firestarter, you can make do with wetter wood.

But, at any rate, you can't just chop a tree down and use the wood for burning. Or construction/manufacturing, for that matter. Wood deforms while it dries so you again need to dry the wood if you want to be able to use it for anything (and this time around you MUST leave it for AT LEAST 6 months to dry).

I would also leave making stone tools to the experts. That shit's complicated. You wouldn't think it is, but it is.

I think any "post-apocalyptic" scenario would have to address gain and storage. It's not reasonable to expect what you can generate to exactly match what you consume.

So, you either store energy in something that can then deliver it at a greater rate (than you can store it) but shorter duration.

Or, you store it at a higher rate and draw on it at a reduced rate.

The former might be something like using a PV cell to power a pump that moves water (a little at a time) "uphill"; the stored potential energy later recovered by letting that water "flow" (or *fall*!) back down at an accelerated rate.

The latter might be winding a spring and letting it unwind, slowly, into your load.

[Of course, each of these can be used in the opposite manner; the point is the mismatch between production and consumption -- and the reliance on storage to facilitate this]

Flywheel is tough because you can't typically "incrementally" store energy in it (at a rate that would overcome friction losses).

Well, if you must.

Flywheels are commonly used in big motor/generator power plants used by telcos and ISP's. They can supply huge amounts of power for fairly short periods. The problem is that they rely on motors and generators to operate, neither of which are not very efficient. Using conventional roller bearings and an open air installation, the bearing and air friction will cause the flywheel to lose about 20% of it's stored power in 1 hr and 40% in 2 hrs. The only way to run longer than that is magnetic levitation bearings and vacuum packaging.

For the bug out bag, the gyroscopic effect should be lots of fun. You want to turn one way, and it wants to keep going in its own way. Try walking around with a spinning bicycle wheel for a hint on what it will be like.

As for the original problem, I think a steam generator driving a turbine and generator is the way to go. In any emergency, you can usually find something to burn. Build up some steam and the generator charges a battery or runs the devices directly (with a suitable regulator or inverter). If you have sun, use solar. If at night, start a fire. If you don't like the noise, move it outside. Might as well do something interesting while waiting for civilization to return to normal.

Lynx Steam Generator - Making Electricity Plenty more on YouTube.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Aleksandar Kuktin:

Well, furniture, there your go.

:-)

I have done some masonry build a wall etc. I can build a small stove without cement no problem. Even a shelter.

I remember that book 'Around the world in eighty days' where to get to England on time they started burning the wooden parts of the steam ship.

Life is about improvisation really.

When the nukes drop, most will die of shock being unable to adapt to a life without pills and without expert help for everything. Batteries are your last worry. Even 'tricity.

As far as batteries goes, in the Tritium decay experiment I just backed up with Duracells Alkaline, they just work:

Aleksandar Kuktin:

Actually that is complete BS. I had a hedge against the house, it got bigger and bigger. So one year in December I cut the thing, it came dowm, a HUGE heap of wood and leaves. we burned it in a new-years bonfire. Flames meters high, next year it was forbidden... :-)

OK some car went up in flames too and what not, left a spot on the bridge... New bridge was build.

Hello?

Did you ever see a bush fire?

6 month my foot.

A few years ago, I tried to set fire to some firewood I chopped down a few hours previously. The "fire"wood was utterly unimpressed. It did burn down just fine the next winter, though.

Better idea than the flywheel.

On a sunny day (Mon, 18 May 2015 09:18:26 +0000 (UTC)) it happened Aleksandar Kuktin wrote in :

Poor some petrol over it.

Bad idea. Significant risk of starting a fireball and burning to death.

There are actual cases of this being reported in the mass media every now and then.

Petrol accelerators do not work. It's not the petrol that's burning. It's the vapors. These heat the surface of the green (wet) firewood, which causes the water in the wood to evaporate near the surface, which cools and extinguishes the petrol fire rather quickly. You can see the water as "foam" coming out of the ends of the logs, if you throw a green log on top of a existing hot fire. Green wood is between 30 to 70% water by weight. Dry firewood, ready to burn, about

15%. Just to make it difficult, most of the water is in the sapwood, near the surface. The ability to dry firewood also depends on the relative humidity.

You might be able to burn green firewood if you mix it with dry firewood. I've done that a few times with poor results. The water in the green wood cools the fire, reduces efficiency, and coats the flue pipe with creosote (condensed oils and sap). There's an art to wood heating and I suspect I've made every mistake possible during my learning experience. Burning green wood is one mistake that I don't plan to repeat.

I heat my house solely with wood heat (except for the electric bathroom heater). Typically, I burn 2 cords per year. About 1 cord this year thanks to global warming. I used to drop, buck, split, haul, and stack my own firewood. It's a HUGE amount of work best done by someone younger and better physically and technically equipped: It also takes at least a year in the forest for the wood to dry sufficiently to burn. I let mine dry for 2 years. After about 5 years, the wood begins to rot, so accumulating firewood for long term storage is problematic.

Moisture Relations and Physical Properties of Wood

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

On a sunny day (Mon, 18 May 2015 15:00:37 +0000 (UTC)) it happened Aleksandar Kuktin wrote in :

There is significant risk crossing the street too, there are actual cases of this being report...

As with all thing: Use Brain. use imagination and basic understanding of physics to extrapolata on what you are doing.

That goes for everything.

I did see somebody on youtube pouring liquid oxygen on a fire IIRC. was discussed here years ago when I started making some. :-)

People have been making things from green wood for a long old time, houses included.

Bone's easy to make knives from

NT