Intro Battery Bank and Salvaging

Hey Woodgassers. I’m thinking it’s time to invest in a decent deep-cycle battery(s) for emergency/camping usage since we’ve already had 3 power outages (2 of which were >48 hrs) this year, and expecting another tonight/tomorrow.

I have a 900/750W inverter that can power my mini-fridge/freezer, the pellet stove I just “fixed” (helps to plug in ALL the sensors/wires), and a few LED lights. I wish I had one that could comfortably power my series of 10-Amp (1,200W) power tools, but that’s on the future still.

I know it’s bad for automotive batteries to get drained down repeatedly, so using my truck battery and then getting a jump-start isn’t very feasible.

I would probably go for an RV/Marine deep-cycle battery over things like forklift batteries, because I would like to retain the ability to toss it in my vehicle for camping usage, as needed.

Would folks please chip in their suggestions/experience on which battery(s) I should be looking at?

Secondly, do I need to get a special/dedicated charger for these (no solar/wind/hydro power, except from PUD grid) or could I just hook it up to my truck, either with or without the standard battery? If I can just “jump charge” it, what’s the optimal way to do so?

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Hi Brian , for what its worth I still think Trojan deep cycle 6 v T-105 or the L 16 are the best battery’s I have ever had, I bought 8 of each from the scrap yard and when they were 10 years old, and got them up to a decent state of charge , but no way will you be able to "toss " these heavy brutes around but they will stand up to some abuse on a off grid setup , in the 4 years since I got them only 1 T105 on the 12 volt system has now failed , all the others are still going strong .
Dave

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Hi Brian,

If you don’t mind the maintenance, flooded lead acid are the longer lasting choice. If you don’t want to check on the water levels than get AGM. I wouldn’t bother with gel or other types.

I like the rolls batteries and you will find the trojans at the bottom of the list.

To answer your second question, I would get something like this and a solar panel. You can get a battery maintainer that you just plug into the wall. I don’t know anything about the linked brands.

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Brian using a 900 watt modified sine inverter I would probably feel your best bet would be a deep cycle marine battery. If your main charging method is the truck then get a battery isolator rig allowing you to charge both batteries separately without draining each other. An even better scenario is have two in rotation. In the event of power failure you have more then 2 kw at your disposal and can hook both up to the truck as needed to double your recharge rate… eventually a bank of l16s should be the goal of course…

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Hi Brian, I will get a lot of crap about this but here goes: get yourself a good hydrometer, and a volt meter that you can test individual cells, go to a salvage yard, and buy good, but cheap car batteries. These won’t last as long, but you can buy 10 or 15 to one good deep cycle batt. I have even taken batts. that aren’t very good desulfate with epsom salts and used them for up to 2 more years. When money is tight you can do other things other ways, not ideal , but gets the job done. there is always more than one right way to do things. Be careful, always in a well vented area when charging (hydrogen gas). Al

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All great suggestions guys. Brian you will want to evolve from these ideas as you are able to afford.
I’ve done this drive the vehicle/swap in/out in the past a lot with lead-acid truck/equipment batteries.
Used to be 8D and 4D 12 volts.
Then it was 30H’s.
Later 31’s top stud types.
Depends on what you can get.
If you vehicle carry these you will want them in individual solid bottom plastic tray boxes. Make top of edge hadles for these boxes. KEEP the battery in the box. Move the box.
Set them all up with marine RV stud terminals. Wing-nut off and on eyed cabling.
Used batteries and eventually you will have one hydrogen blow on you.
This is most prevalent at attaching on and off. Forced fan vent well and you’ll never see this.
Enough forced charging of used batteries and eventually you will have one either with mushy internal broken terminal, cracked internal cell crossover current flow arc; or internal plates short lite off and pop on you. Why I recommended the no post stress wing nuts. And you will have done nothing wrong but just be there.
Of course the battery manufactures and safety folk insist you should have rubber gloves, rubber apron and a full face shield battery handling.
Ok to use dedicated leather gloves.
Really should use a face shield. At least head-turn look away connecting and disconnecting.
Have rinse water available. Box of baking soda.
Touch a lead acid; touch cotton. your cotton will be well ventilated after the next wash.
Wool, nylon are good. 40/60 blend good/OK.

I know I may seem overboard. But had five pops between 1978 and 2005 from a distance of 18" to 4 feet.
I figure a rate of 1 in 5000 handled/manual charged connected/diconnected.
Ha! I’m still here!

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Obviously Brian if money is tight you will have to start with what you can. I don’t like relying on scrapyard luck so I still vote for the deep cycle marine funds permitting. As a bonus you can usually pry off the non serviceable caps and add water. You can avoid some of the real problems Steve mentioned by wiring in a permanent dc breaker or marine style battery switch to your second battery charge station. They are nice because you can make your connections to the battery then apply current when further away. As mentioned invest in a case for it and some firm of quick connect/disconnect fitting; I like the 100 amp rated blade type. Build, think, use it, curse yourself for shortsightedness, burn something out, more cursing, rebuild, hopefully get it right, gloat…
Best regards, David Baillie

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It’s not about scrap yard luck it’s about testing before you buy

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Fair enough AL didn’t mean to annoy…

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Thanks for all the great replies, guys.

I should probably note that this is an idea for an early Winter-Holiday gift request, so my budget might be a bit more flexible.

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No worries Dave, just want Brian to succeed,so many let money deter them, when you can do it with a little ingenuity, and help from people that have been there.

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Brian, This might be an idea as well, working on it myself , will sent some pictures…

Secrets of alternators…

http://www.pssurvival.com/ps/Alternator/Alternator_Secrets_2001.pdf

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Al F. could you give a little more detail how you select batteries from the “junk” pile to buy good ones. My wife just went through my shop and took 13 batteries to the junk— got $2 apiece when I found the core value is now up to $10. With my equipment every spring I have to buy a couple of batteries, never bothered with the core.
How can I test to make sure they are “junk”? I try to keep the batteries on charge during the winter and I use both 6 and 12 volt desulfinator type chargers. I have a shop type charger which I try not to use because it puts out too many amps too fast. I have a small 6/12 volt charger that I generally use. I bought two heavy duty batteries for my tractor. One went bad but the other is still good. What would you do to try to rejuvenate the bad one? ThanksTomC

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Hi Tom, 1st use a hydrometer to measure specific gravity, if all cells are low but equal should be able to revive it. Some meters have a prob to put in the cell, should be 2v each. if you have a dead cell probable can’t revive. When you have a good,but weak batt. dump out as much acid as you can, put 10 Table spoons of Epsom salts in 1 qt of boiling distilled water, fill cells equally, top off with clean acid, charge slow for at lest 24 hrs. this works best if the batt. doesn’t set dead too long. Al

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Hi Tom , if I can also mention something else that has worked well for me .
I have used “EDTA” in Deep cycle battery’s , the same sort of method as with Epsom salts but it costs me a lot more as I have to import it from the states to Australia but you can buy it there for around $14 for 1 lb from a company called Trailhead Supply ph 801 225 3931.or 801 226 6630
I think as long as the plates are good and not shorted out or buckled then this will help too
Dave

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Ok guys; I said I had two batteries in my tractor and one went south and the other is good. I finally got the cap off from the battery and there is a metal plate where the acid is support to be kept filled to. I could see no liquid in the cells. What do I do? Fill them with distilled water. Or do I fill them with acid? Or do I do the thing where you empty the cells and fill them with the mix of epson salts and distilled water. I don’t have a clue how that works.

What does EDTA stand for or what is it? Thanks allTomC ( this was a very expensive batter and I hate to loose it.)

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So, if the battery case is not cracked you should add distilled water only to a cell that is low. According to every guide I have ever read or heard of you do not add acid unless it spilled. Fill, charge, equalize. Feel free to verify online or any battery maker’s website.

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Hi Tom , sorry I didn’t put the full name term for EDTA as I thought you would Google it and its uses, this is what its full name is ethylenediaminetetraacetate .
when I bought this it came with the data sheet and instructions for mixing and amounts , it looks like a white powder similar to Epsom salts that you mix with warm water to dissolve before filling each cell .
Dave

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Tom, could you post a picture of the battery ? especial from the battery description.

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Yes Koen I can post a picture but to get a picture worth anything, I would like to know what you are looking for in the picture.

D&B Ok I Googled EDTA. Didn’t find out much about using in a battery, but my gracious; if that works it could save me about $1000 a month in medicines that really are not curing anything, just prolonging my life a little. Sounds great, but I would be afraid to try it for how it would react with the meds I am taking. Like high blood pressure — if both worked it could “tank” my blood pressure. As “iron chelate” I used it on my yard in Calif TomC