What's in a name? With Industrial/Forklift batteries everything you need to know.

Trukinbear

I had some blood flow to my brain today (LOL) so I thought I'd share what I'm remembering while I remember it. If this is old news to everybody, or I wrote something just like this before, please disregard it.

Industrial batteries will often be named as the one in my profile pic 24-125-11 (NC-S-P)

The forklift battery is a large metal case that contains this number of cells interconnected by plates - usually, the cells are individually replaceable, and one or two-man carryable (individual cells). Though the case is often made of 1/4-3/8" steel you cannot just hook a chain to the eyes at either end and lift! Without a distributed lifting bar the chain will just fold the eyes over like ears before you ever get it off the ground. 

NC S P

We can break that down, the first number we'll refer to as 'NC' is the number of cells (mine is 24)

The next number we'll refer to as 'S' is the AH of one positive plate, the larger the plate the heavier the battery is for a given number of cells (mine is 125)

The last number we'll refer to as 'P' is the number of positive plates per cell (always an odd number as there is one more positive plate per cell than negative) the more plates per cell the heavier the battery is. (mine is 11)

In the equation below we take that odd number and subtract one, then divide by two to illustrate number of pairs of plates per cell then multiply it by the size of one positive plate 125


P=Number of positive plates
S=Size in AH of one positive plate
AH=Rating of battery at C-6 discharge rate
V=Nominal voltage of the battery V=CN2
NC=Number of cells total

AH=((P-1)/2)S
V=NCx2

Mine at 24 plates is 48 volts and with 125 sized plates, and eleven of them
Eleven plates minus one is ten, divided by two is five multiplied by one hundred twenty-five AH per plate for my particular battery = 625

So My battery is 48V 625AH at the C6 discharge rate and happens to weigh about 2200 pounds, minus 100 pounds or so for the case figure that each cell probably weighs about 87 pounds.

they come in lots of sizes from 6-55-5 (12V-110AH) all the way up to 36-170-27 (72V-2210AH) and probably way bigger in industrial applications

55AH plates are 17-1/2 inches tall (low profile)
75AH, 85AH, and 100AH plates are 27 inches tall (standard)
100AH(tall), 110AH, 125AH, 140AH and 155AH plates are 31 inches tall (tall)
170AH plates are 31 inches tall but are wider (wide tall)

Plate numbers range from 5 to 27 *maybe 31

Number of cells
6=12V
9=18V
12=24V
18=36V
24=48V
36=72V

Trukinbear

Forklifts are funny in that they need a very specific size battery, nothing else will fit. Keep this in mind when shopping for a forklift battery for your solar application that you may be able to negotiate a smokin' deal on an odd size.

BB.

Thank you Trukinbear.

Sincerely,
-Bill

Photowhit

The P is the total number of plates, and amp hours of a positive plates is based on surface area, not height.  But good info!

Also if you are ordering a new battery, you can have them put on 'flags' rather than wires. This can help with some installations and remove an unseen connection.

Trukinbear

Yes, it is the surface area - and they are broken down into height groups but their other dimensions are different -  there are no 27" tall cells that are over 110Ah, and nothing over 110Ah is under 31". Generally larger plates in AH are taller, and more plates is wider. I added this because the taller heights are less common and are pretty much only in the much larger equipment, or some large standup pallet jacks, and maybe the best bang for the buck. Keven at Monterrey will even sell you individual cells in any of those sizes for those who want to move it more or less by hand and assemble in situ. 

BB.

For reference (because people are talking about the company for industrial batteries and single cells for forklift batteries):

http://www.montereybattery.com/

-Bill

Trukinbear

I have no connection with the company other than being a very happy customer.

Trukinbear

The taller cells like in my 125 series battery are noticeably taller.

Photowhit

BB. said:

For reference (because people are talking about the company for industrial batteries and single cells for forklift batteries):

http://www.montereybattery.com/

It's likely relabeled GB batteries. They use the same bad multiplier to set 20hr rates. More realistic multiplier would be 1.3 or 1.35 rather than 1.6-1.7 x the 6hr rate to calculate the 20hr rate.

I still think forklift batteries are the best value for long term storage. lithium will likely come down enough to make them a better value in the next few years. I'm 9+ years now on mine, it's doing very well for the abuse it's taken and allowed my system and situation to produce energy below 30 cents a kWh (including a large percent of energy used in essence directly from the array.

New_Mexico_Will

Looks like they haven't updated their website in close to 4 years.  2017 is upon us!

Trukinbear

Photowhit said:

BB. said:

For reference (because people are talking about the company for industrial batteries and single cells for forklift batteries):

http://www.montereybattery.com/

It's likely relabeled GB batteries. 

I guess it's possible his cheap (lower warranty batteries) might be GB, but I saw them (at Monterey) making three big batteries on my tour while I was in San Leandro. Yeah, don't let the website fool you, so what if it isn't updated, some people spend more time with their customers. I actually didn't start out at Monterey, I actually started with GB and couldn't get their salespeople to even talk to me about a singular non-specific battery. I decided to go with a regional manufacturer I could drive to and speak to a real person - Kevin spent half a day with me and made me feel as important as a big corporate customer. 

Photowhit

Yeah, GB was a bit of a nightmare dealing with, I was just going to get 2' longer cables and deal with pulling the connector, but the sales person didn't understand that. I have a good bot of 2 and 4 gauge wire, so I asked them if they could make it with flags. The salesperson didn't understand that either, until I sent her web shots and links to their web site... 

I kept a copy of the contract which stated a total price "including all taxes" as they were shipping it, they were responsible for state sales tax, which I don't think got paid.

...but once we got settled, it was made and delivered inside of 10 days, I want to say a week later. I hadn't been warned about their over stating the 20hr capacity, but it is pretty easy to see when you compare to other tall cell batteries hourly rates... 

Trukinbear

The conversion jives with the one SMA sent me when I questioned if the capacity of the battery could be wrong. Kevin says that forklift batteries are made for regular DOD of 80% which is why they are rated the way they are. IDK, I just know I get the same number no matter who I ask. GB couldn't wrap their head around that I was in California (by 20 miles) but wanted to pick up a battery in person in Oregon, and that I didn't know what battery I wanted - the prices are on the Website... Obviously, I wanted to negotiate with someone.

Photowhit

Trukinbear said:

The conversion jives with the one SMA sent me when I questioned if the capacity of the battery could be wrong.

I've never heard of SMA making a battery...lol.

Here's a link to a thread where I posted some conversions in the 2 reply, highest I found was 1.4x;

https://forum.solar-electric.com/discussion/354176/forklift-battery-sizing-and-prolonging-life

Somewhere I had hunted down Crown's conversion multiplier, I can't find Crown's site specs right now, but from a retailer, they rate their 12-125-13 (a 750 ah at 6 hr rate) as a 935 at a 20 hour rate, a 1.25x multiplier;

https://readymaderesources.com/product/crown-12-125-13-industrial-fork-lift-battery-24-volt-935-ah-call-for-shipping/ 

GB rates their 12-125-13 at 1182 ah 20hr rate.

Trukinbear

It was their conversion chart, plug your C6 in at the top and the C20 spits out at the bottom just like everyone else's it showed a conversion of 986 - I don't care if it correct in the real world at all, I care that it is the conversion for the number my SI wants to see. SMA does make batteries BTW, just probably not FLA. 

Trukinbear

Bumping my C20 from the 775AH I had programmed (because my book said C10) to 986AH was the first thing SMA tech had me do. Maybe it is wrong, but my Sunny Island is finally acting right.

SafariParkEarth

I'm looking for a good new/used forklift battery supplier in Northern Arizona. I have a 2004 Raymond 36v r30‑c30tt. It is also going to be my SHTF backup battery but they are super expensive from what I see.