Forklift batteries for a solar trailer?

MrWizard wrote:
How much do these batteries weigh, what happens when it's time to replace them
How much money is a 48v charger cable of bringing them to full charge
Your talking about 60v for an equalize charger at how many amps

How much money for the project ?

Not saying this can't be done, you Can build this thing, but is it the best way to go

I would be inclined to use surplus Telco 12v agm batteries, instead of forklift batteries
Just put four in series 48v 132 amp hrs, they tend to be hardly used, instead of worked hard and reconditioned

Mr Wizard is very wise here.

That probably is a better option, because telcos tend to be very conservative on battery life, so the batteries powering the NEBS stuff tend to be changed often.

There is also another downside of the huge forklift battery that I didn't realize until I looked at one in person recently. They are huge, and unwieldy. If something really bad happened to the trailer (which wouldn't be enclosed due the off-gassing), I'd have to have someone come out and deal with the two tons of potentially hazardous mass. With the above telco batteries, I am able to at least sling them somewhere in case of emergency, like my pickup truck bed.

Ah well. I'm glad I ran this up the flagpole, because it seemed like a good idea, but physics and Murphy are merciless beasts, and I don't want to risk being on the wrong side of either.

I'm curious, how large is the trailer you are looking at?
Since the charge rate is roughly c10, or amps at 10% of total amp hour rating, if your panels can provide 10 amps @12 volts for each 8 sqft panel, your looking at anywhere from 360-400 sqft in panels needed to recharge to a high rate. Trailer roof and some type of extensions would be needed, maybe a large set of slides like drawer slides so they can retract for travel. Just curious what your looking at.
Maybe my math is wrong, but it seems a little large.

Have you considered the cost of the battery?? When I replaced the 36 volt battery in my forklift, it was $4,200.00 with my old battery. I think the 6 or 12 volt battery is the more economical way to go.

Make your fillings fall out potholes, speed bumps etc. All the forklifts I have ever seen complained when passing over so much as a concrete expansion strip.

Fan sucking clean air is safe. Fan sucking battery fumes ties hashimaki around forehead and commits seppuku.

The problem is decent shape forklift batteries are not easy to come across. One from one lift, two from another, and...

The different batteries hate each other. They die, you pay.

Hi Mex,

Plate warping in tubular cells from the jolts (i.e. high demand)? Or do you mean mechanical vibration?

My favorite bank is still 800 amp hour two volt cells in series (Surrette). At 48 volts the jolts are not so bad for a 1200 watt load. Unfortunately I have a beer budget, so this may remain a dream until I win a lottery.

Is corrosion the reason for pushing air rather than sucking it?

The gasses you mention are why I don't approve of unvented battery boxes for AGM jars. They tend to be pretty deadly with even short exposure times.

Don, those batteries do not like to see hundreds of sharp jolts. It would be wise to avoid a buckboard ride. My system trades volts for amps. 12 cells in series, 1625 x 2 amp hours paralleled batteries in a 12-cell string.

Food for thought: Exactly how do you plan to run an equalization on these cells? See if these batteries are "Tar Top" with over the cell connectors.

Let's imagine they are 600 amp hour cells. Five percent of 600 is 30.00 which means you need to configure a 30 ampere current all the way up to 2.666 volts per cell end point. Don't feel picked on. My 3250 cells at 5% = 162 amperes constant current to 2.666 volts per cell. Thank god for a hundred sixteen pound 240 vac transformer. Equalization performed, paired cells, by paired cells.

Large cells emit large amounts of H2S, SO2, and H2SO4 vapor. Vapor dissolves wood, and assaults all but exotic metal. You may avoid grief by getting the interior of the trailer coated with non asphaltic pickup truck bed liner coating. The inside of my gen shed was painted with light gray Sears two part epoxy paint. Ventilate the enclosure with fans pushing air from outside to inside, exit vent high and as opposite as feasible. My gen shed has over 240 watts of forced air intake. The fan needs to run for 1/2 hour after charger shut down. That means using a battery voltage fan or fans.

Many utility motive batteries have .250" plates.

kerrlakeRoo wrote:
If you are going to look at something like that you may want to also look at the industrial scrubber or sweeper batteries,
Batteries plus sells the Duracell units 228 a/hr for about $270 I think. Similar footprint to a group 31 but taller.

My son's in-laws have one of these big floor scrubber things on their RV. They love it. It's referred to as a 8D battery. Only disadvantage is the weight in a single battery.

wa8yxm wrote:
. Why 12 volts? Well a lot of stuff used in RV's is designed for 12's so why waste energy converting?.

I don't think conversion losses from a 1000ah 48v battery are going to be significant.

seen this couple years back at roosevelt lake in arizona ,guy said it worked great.

I would stick with 12 volt designs, and yes, they make those for Fork LIfts as well.. Why 12 volts? Well a lot of stuff used in RV's is designed for 12's so why waste energy converting?

Now.... I have indeed used a fork lift battery. the one I used was 12 volt, and I can't tell you the capacity or the weight.. It was a Flooded Wet Cell type (Like the golf car batteries) I have also seen Sealed types and AGM's used on Fork Lifts but those were not ones I used.

The Reconditioning company charged it and loaded it on the trailer I rented.. I towed it to the site where my ham club was running Field Day We ran everything off the batteries. 3 2-way Radios, Rotors for one or 2 antennas (3rd was fixed) Lights for 24 hours Shop said the battery was down about 10% the following day

IT WAS NICE. .no generator noise. NO "AC-Line noise" NO AC-Hum. ANd we placed top in the state (In the battery class) of course.