charging forklift battery

miket
miket Registered Users Posts: 14 ✭✭
Looking at upgrading my battery installation from 420 AH of L16s to an 800 AH 12-85-13 traction battery.

I have a Outback MX60 and 1000 watts (@ 48 volts) of PV array charging at 24 volts.

Backup charging is a 24 volt/200 amp Balmar set up as diesel powered charger.

What does the traction battery listed need in amps for equalization? Any rule of thumb here?

I have a 7.5 KW Cummins-Onan Deisel on the side as well.

mike

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: charging forklift battery

    Welcome to the forum.

    I see a couple problems right off so ...

    Instead of upgrading your batteries maybe you want to upgrade your array, as the existing 1000 Watts isn't even enough to fully charge the 420 Amp hour bank much less an 800 Amp hour bank.

    I don't think you meant to say "Amps for equalization" as equalizing is a matter of holding a higher than normal Voltage in order to bring up the Specific Gravity of low cells.

    Battery FAQ's are a good read: http://www.windsun.com/Batteries/Battery_FAQ.htm

    As for the forklift battery you mention, you need the manufacturer's specs for preferred charge rate and Voltages.

    Some of the other forum members have used or are using forklift batteries and should have better insight to them.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    Re: charging forklift battery

    Your question of what a battery needs in amps to equalize is not really an issue!
    Doing an EQ is always done on a charged battery! An EQ uses less than 400 watts.

    I am guessing that what you really need to know is how will you charge the new battery.

    I have never believed, and have personally tested over time more than once that there is an equation that tells you the charge rate for a given battery. Batteries last longest when charged daily, not deeply discharged, and slowly charged.

    The question you really need to ask is, if I get this larger capacity battery, and I use more energy, what do I need to do to charge this battery? You have to know the amount of energy that you need.

    So where is latitude 39 Mike?
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: charging forklift battery

    I don't think you have too small an array for a 420 ah battery, but I do think you will be too small for an 800Ah battery. 1000watt array at 24 volts(nom) should put out roughly 25 amps an hour w/PSM controller and perhaps as much as 30 with a MPPT (very rough off the top of my head) so about equal on a sunny day to your max draw.

    I've been looking into/planning for, a fork lift battery. I too will have a 24 volt system. I'll have @2000watt array supplying the battery.

    Most forklift batteries want to be equalized more often than other FLA batteries.

    I have looked into this and batteries do appear to be cover as part of a solar system and hence qualifies for the 30% tax credit. NAWS is great and sells a couple Crown forklift batteries Here.

    This is likely too big for me (and you) I've found that GB Industries sells direct with shipping in the lower 48. I have a link to the price list from last fall Here. Please note this may be an archived page, I only see a price request on their site currently. Also price does not include a lift bed truck (+$150 for me) an Taxes they do business in most states. Also the lift bed just gets the battery on the ground, not necissarily installed. I have access to a backhoe...

    I like the idea of getting a 30% discount on perhaps the last battery I'll need and I'm sure someone will come to their senses and quit this anti "green" credit. I'm just a poor capitalist:D

    Monitors Please feel free to Edit if you need to just wanted to pass along info and ideas.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • miket
    miket Registered Users Posts: 14 ✭✭
    Re: charging forklift battery

    I'm 90 miles north of Sacramento, in the hills.

    What is driving this is that I lost my 4 year old battery bank that had been performing just fine. I'm not sure the failure. My system has been trouble free the last 4 years. Basically, I boiled the water out of them within in 2 weeks of my last service which I do on the first weekend of each month.

    My Trimetric shows a full charge on sunny days and if I get near 80% on the sunless stretches I always run the dc charger till I get "float". Usually it take 3 to 3.5 hours to "float" from 80%.

    I use 1 to 1.5 kw a day in the winter, a bit more in summer with the Solar chill evaporative cooler 130 Watts/Hr. When in energy conservation mode is far less. I can get by on 400 watts a day with little effort at all!

    Something has changed and I just don't quite know.

    I equalize the L-16s monthly on service day. The batteries have been down to 80% five times in all these years (I count the instances!)

    My insolation is compromised due to trees but I usually get a least 1.4 kw on the winter days. Summer days I see closer to 2kw. I just use less as a matter of course!

    I may add another 500 Watts of PV (4 KC 130s) since I am locked into groups of 4 panels for 48 volt strings. I suppose I could use four 80 watt panels (which I can get a helluva deal on).

    Guess I need to revisit the numbers and collect some more data.

    mike
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: charging forklift battery

    Do you reset your Trimetric after each equalizing?

    It may be that you've lost some capacity and that your fully charged and the trimetric doesn't realize that your battery bank has reduced capacity... Without checking the Specific Gravity (SG) of the batteries, you might well have created more problems by trying to add charge to a fully charged battery bank.

    Just a thought, I realized I'm more of a touchy-feely user and have a trimetric around somewhere but haven't hooked it back up, since taking it done when changing out an inverter. Even Cheap L16's should last 5 years, but perhaps your just due...

    My guess is your just letting the charge controller do an equalizing charge each month, this is a maintanance type of equalizing. perhaps you have a single cell getting really bad and need to do a charge based on SG, check out the battery FAQ's here (someone will likely be along to provide a link shortly...

    Regaurdless you might well get another year or 2 out of dieing batteries, as they slowly loose capacity.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    Re: charging forklift battery

    Mike,
    Once a month EQ is excessive. What battery make? When you say 80%, it is not clear, to me if you mean charged or discharged. Bring on the data! Nice day today up your way I bet! The southern sierra has been in a snow at night and daily deep blue skies.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • miket
    miket Registered Users Posts: 14 ✭✭
    Re: charging forklift battery

    "What battery make?"

    Trojan L16s.

    "When you say 80%, it is not clear, to me if you mean charged or discharged."

    Rarely ever go below 80% fully charged. At 80 percent I gets a full charge till it "floats" using Program 2 on the Balmar 624.

    The data log in the MX60 is helpful but not real useable. I need a damned datalogger of some sort.

    I haven't reset the Trimetric monthly, preferring to maintain the lifetime battery stats. I set the amp set point for a full charge at 2 amps or less. Initial rate of charge from 80 percent is usually in the the 55 amp range until full bulk voltage is reached. An so on and so forth. Standard Balmar routine.

    I think maybe bumping up to 1500 watts PV may be the right approach. That is potentially about 50 amps of charge at 24v volts. That may cover me in the lean days of winter when insolation is not so good.

    I need to look at the MX60 book regarding the PV String Voltages to. Getting the early day charge is pretty important.

    mike
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: charging forklift battery

    I hate to sound like a broken record, but Trojan does recommend a peak charge rate of 10% for these batteries in order to remix the electrolyte and reduce sulphation.

    So 42 Amps @ 28.4 Volts is 1192 Watts. Factor in the typical derating and you get the need for 1550 Watts of array.

    Likely the batteries' life was shortened by chronic undercharging. That's the #1 problem with FLA's.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: charging forklift battery

    Sorry, you are correct about Trojan batteries, here's a link. Please note this is just the recomended charging rate and on solar it would be rarely exactly there.

    Indeed these are guidelines, they also suggest not storing batteries below 32 degrees, while I've never seen that this will cause damage only a reduction of capacity down to the acid's freezing point, typically well below zero. My 5+year old golfcart batteries survived -13 and -10 degree nights this winter and have always been stored outside. As these batteries are beyond their expected life...

    I did/do know they (Trojan) recomend only doing an equalizing charge when the SG is well out of specs, While Rolls suggests at least every 6 months. In the past a charge rate of c12 or 1/12th of the capacity of the battery was a desired standard. Indeed my 4 golf cart batteries were charged from roughly 220 watt array for the first year of their life. (12v with 2x2 batteries now 24v string)

    It would depend on usage, I would suspect the unmonitored(we haven't heard how eqauizing was done yet) would mix the electrolite for any "undercharging" it also appear the capacity has been monitored closely. Though perhaps the equalizing messes with their special mats?

    The sun will shine tomorrow, homemade pizza for lunch in the toaster oven, and brownies while the ovens hot, I can't wait. We've had a week of poor charging/sun.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: charging forklift battery

    And of course "storing" is not the same as "using" at 32F or less. I've never had any trouble with batteries left in our -40 Winters because they were in an insulated box and kept charged.

    But one of the things we too often forget is that the net charge rate is what goes in to the battery minus what is drawn out at the same time. None of us shut down our systems while they charge, so even with "ideal" targets the actual charge rate will be a tad lower. That's why I don't like to see systems with a potential for only the minimum 5% rate.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    Re: charging forklift battery
    And of course "storing" is not the same as "using" at 32F or less. I've never had any trouble with batteries left in our -40 Winters because they were in an insulated box and kept charged.

    But one of the things we too often forget is that the net charge rate is what goes in to the battery minus what is drawn out at the same time. None of us shut down our systems while they charge, so even with "ideal" targets the actual charge rate will be a tad lower. That's why I don't like to see systems with a potential for only the minimum 5% rate.

    I wish I could say I agree with this Marc, but I really never have and can prove it!
    First of all people can shut down their systems to charge ( search mode) and many do by not using energy during charge time. It is the winter dance! There are other things in life beside racking up KWH.

    The 5% rule is as wrong as is the the 10% rule if it is not in context. If you are not deeply discharging then you do not need that amount of charge. It is the way that offgrid systems grow over time. The point where this goes wrong is when folks use more than they can charge pn a regular basis. It takes discipline but it is easily done.

    I know you guys have to deal with general rules here but there are always exceptions! I just had a deep cycle die that just turned 19.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: charging forklift battery

    Dave, if I've said it once I've said it a thousand times; solar is highly site-specific!

    And yes we do have to deal in generalities here. Otherwise you get unhappy returns from people wondering why their system doesn't perform at the fringes. I'm one of those who "cheats" on the rules myself, but my high altitude and over-all cooler temps give my panels something like 82% derating rather than the "typical" 77%. And my daily load-shifting squeezes out Watt hours that otherwise would be missed.

    Let's not forget that the 5%-13% rule is a peak target, not constant charge rate. Most people do not shut down for charging; they're looking for "set it and forget it" systems. If we tell them something otherwise ... disappointed readers can be so vengeful!

    The number 1 problem we see around here is insufficient charging due to too small array. Number 2 is underestimating loads. Number 3 would be overestimating insolation. All things considered, I think we'll stick with the rules-of-thumb for "typical" and leave out "exceptional".
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: charging forklift battery

    for the record, the 5-13% rule of thumb is what is being delivered to the battery and not what the pvs provide, for loads may be on during charge that would take a portion of that % away from the battery. those %s are somewhat arbitrary, for somebody at 4.9% may not have to buy more just to be in that range and will vary by install and even battery type. don't forget that the electrolyte needs to be stirred up on many fla types and, even though one may not need to replace much in the way of ah because of not giving a deep draw, the battery will suffer when only giving back a very small % of charge at all times. does it need to be stirring the electrolyte all of the time? no, but it should be stirred up at some occasions and if you have the pvs to do that occasionally then they will be left on to deliver this capability at all times for who would hold back on some of their pvs just to give a small % charge rate due to a small discharge to the battery? simply put, if it's needed you get it and if you have it you'll use it.
    there's a lot of ifs, ands, and buts to this, but i would not say the rule of thumb is wrong given it is to be what the battery gets and the only context may be the charge parameters governing the battery because of its type.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: charging forklift battery

    So I have a @2000 watt array, and will purchase @810 Amp Hour 24 volt forklift battery, so 2000 /35 volt = @57 Amps X .65 (largely PWM controller) = 37 Amps or about 4.5%

    So I'll run the test for you and report back, hopefully in 20-30 years...

    For the record, I can live with 500 watts of panels for 9 months out of the years, it's really only the 6-12 weeks of summer that I use the extra. During that time I also have additional charging hours. I will play though, it will be neat and save propane to run the toaster oven in the evening, though I'll still likely only do this with a sunny day to follow.

    A reminder on the forklift charging, we are responding to forklift charging thread... They like to be equalized more often.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    Re: charging forklift battery
    Photowhit wrote: »
    So I have a @2000 watt array, and will purchase @810 Amp Hour 24 volt forklift battery, so 2000 /35 volt = @57 Amps X .65 (largely PWM controller) = 37 Amps or about 4.5%

    So I'll run the test for you and report back, hopefully in 20-30 years...

    For the record, I can live with 500 watts of panels for 9 months out of the years, it's really only the 6-12 weeks of summer that I use the extra. During that time I also have additional charging hours. I will play though, it will be neat and save propane to run the toaster oven in the evening, though I'll still likely only do this with a sunny day to follow.

    A reminder on the forklift charging, we are responding to forklift charging thread... They like to be equalized more often.

    Thanks! I thought there were still a few who thought of specifications as a guide to interpreting characteristics and not cheating. I started with 200 watts for several years and have worked my way to near 3000 watts. I never use anywhere near the recommended charge rate because I do not use much energy, unless I want to when the sun is out!

    About half of the 45 offgrid folks I am involved with are small and grow over time. The other half are turnkey systems where the moderators advice is valid. Some very beautiful systems in even more beautiful places.

    Photowit, I can't run the toaster in the evening until I win the bet for making this bank last 14 years. It is a very, very nice bet BTW, with a very old mentor.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: charging forklift battery

    Fun stuff, I doubt anyone would believe me if I told them I made a couple home made pizzas, corn bread and brownies running my toaster oven for 2 hours the other day with my tiny 210amp hour 24v 5+ year old battery bank... of course it was between 1-3 in the afternoon and I have a way over sized array for my current tiny battery bank, Only 1300 watts connected currently but it cycles on and off and runs close to a even by the end of a couple hours.

    How long do you need to wait for your toast?
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Ralph Day
    Ralph Day Solar Expert Posts: 1,019 ✭✭✭✭
    Re: charging forklift battery

    Sunny lunch time toast or midnight snack toast (battery toast)?

    Ralph
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    Re: charging forklift battery
    Photowhit wrote: »
    Fun stuff, I doubt anyone would believe me if I told them I made a couple home made pizzas, corn bread and brownies running my toaster oven for 2 hours the other day with my tiny 210amp hour 24v 5+ year old battery bank... of course it was between 1-3 in the afternoon and I have a way over sized array for my current tiny battery bank, Only 1300 watts connected currently but it cycles on and off and runs close to a even by the end of a couple hours.

    How long do you need to wait for your toast?

    I have toast now with a griddle on the range! But your question answer is four more years to win the bet. My first set of Rolls just had a failure of one L16 at 19 years. Using small amounts of energy and always completing charge is as old as battery technology itself.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: charging forklift battery
    I hate to sound like a broken record, but Trojan does recommend a peak charge rate of 10% for these batteries in order to remix the electrolyte and reduce sulphation.

    Marc, I do not want to challenge you, BUT, in my experience, the mixing of electrolyte does not really occur during Bulk, but rather, in Asorb. And, really, then in the later portion of the Asorb cycle, when the cells are most vigerously bubbling.

    The C/10 (or greater) charge currents are reputed to open up more of the active plate material, which helps maintain capacity, and IMHO, this does not need to be done in each charge cycle. Probably monthly would suffice quite well.

    For battery banks that are lighty-cycled (shallow depth-of-discharge), The bank might not even come close to accepting the maximum available PV charge current, as the charging occurs when the sun has not reached the optimum angle. C/10 might be available at local zenith of the sun, but, the bank was fully charged at a lower current. perhaps hours before the local solar maximum for the day.

    EDIT: However, generally, Forklift batteries need higher charge rates than other flooded batteries. Always follow the guidelines specified by the manufacturer of the specific battery.

    Just my personal observation, MMV and so on. Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: charging forklift battery

    Vic; I was in fact relating Trojan's recommendations. You can argue reasons with them if you like.

    Even though we don't go in to the details often, that 10% figure is a potential peak target, not a constant charge current. It's a matter of "if you've got the potential and need it, good. If you haven't got it and need it, bad". Since more often then not we get posts from people whose systems don't meet this criterion and whose batteries are ruined as a result I think it's a pretty good rule-of-thumb to follow. The number of cases of people with too much solar are few.

    Anyone is free to follow or ignore my advice as they see fit. Just remember I've got "I told you so" recorded on a repeating loop. :p

    P.S.: I suspect the need for more frequent equalization in forklift batteries is due to something like internal parallel plate architecture. I've never cut one open, though. Could be fun. John? :p
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: charging forklift battery

    Hi Marc,

    YES, you are correct about Trojan's recommendations. But, here, have often seen the statement about high Bulk currents mixes the electrolyte. In my limited experience, the there appears to be little bubbling aciton in Bulk, but is pronounced in last part of Asorb and quite prominant in EQ. I do believe that the mixing mechanism is the formation of bubbles -- gassing.

    That was my point, but it is reallty a bit of a tangent from this topic.

    My C/10 charge rate can only come from my largest genreator, which is used every few months to do heavy charging.

    Trojan does show 10-13% C20 charge rate for the entire Bulk cycle. And, a bit curiously to me, they show Bulk charges to 90 % SOC, rather than 80% as end of Bulk, noted by some other manufacturers of batteries. It IS always best to follow the advice of the manufacturer of one's specific batteries.

    YMMV, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: charging forklift battery
    ...So where is latitude 39 Mike?

    That's just about where I am too - in Mendocino
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,