Buying new equipment

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  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    #32
    Re: Buying new equipment
    vtmaps wrote: »
    A battery's capacity requires both electrolyte and lead plate. Some batteries run out of capacity because they are limited by the amount of lead they contain, others are limited by the amount of electrolyte they contain. In that sense if you reduce the amount of lead, you will have relatively more electrolyte. Maybe.

    May be that's what he meant. I would say my batteries have more electrolyte than others.

    He said "There is relatively more electrolyte in contact with the plates". The amount of electrolyte in contact with the plates is proportional to the surface of the plates unless there are some obstructions. May be he meant that their separator creates less obstructions. Or that there's more space between plates. Or may be this is a marketing phrase that completely lost its meaning through years of copying and pasting. Hard to tell.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #33
    Re: Buying new equipment

    Thickness of plates contributes to battery life; more lead to erode over time without failure.
    Area of plates ("more electrolyte in contact with plates") increases capacity.
    Volume of electrolyte has nothing to do with it, or else AGM's ("starved electrolyte") wouldn't work. The "separators" in these are a mat of fibreglass; considerably more material than an FLA has.
    Large flooded batteries have more electrolyte of course, and typically have bigger "blank space" at the bottom for the inevitable nasty bits of decay to settle in to so as to prevent them from being "in the way" of the chemical reaction.
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  • Panamretiree
    Panamretiree Solar Expert Posts: 278 ✭✭
    #34
    Re: Buying new equipment
    ChrisOlson wrote: »
    Our shore power charger is a PowerTech IUIa charger. It runs off either 240V shore power or our onboard Yanmar diesel generator. Interstate told me to set the bulk/acceptance rate at 90 amps @ 28.8, absorb at 31.0 for 3 hours, and finish at 31.2.

    Really nice day here today and I'm going to get them installed this afternoon and commission them. The boat is sitting in winter storage and not in the water yet for this year. From the ground to the deck is about 10 feet but the marina has a forklift that I can use today to lift the pallet up to the deck. I got the 4D's out of the engine room and carried them, one at a time, down a ladder a couple weeks ago. I'm not young enough anymore to try carrying the new ones back up the ladder.

    Attachment not found.
    --
    Chris

    Looks like a Trojan, nice boat. exterior looks immaculate.

    Cheers
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #35
    Re: Buying new equipment
    Panamretiree wrote: »
    Looks like a Trojan, nice boat. exterior looks immaculate.

    No, it's a 58 foot Chris Craft Riviera. And she's got a new house power bank onboard now :D

    Attachment not found.

    --
    Chris
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  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    #36
    Re: Buying new equipment
    NorthGuy wrote: »
    He said "There is relatively more electrolyte in contact with the plates". The amount of electrolyte in contact with the plates is proportional to the surface of the plates unless there are some obstructions. May be he meant that their separator creates less obstructions. Or that there's more space between plates. Or may be this is a marketing phrase that completely lost its meaning through years of copying and pasting. Hard to tell.

    Or the plate could be thicker overall for mechanical strength but have a "waffle" surface to expose more area. A spongy surface, as used in a cranking battery, will give an enormous amount of surface area, but the texture will fill in as it goes through discharge/charge cycles. But a large scale texture will go deeper into the plate thickness. It's a tradeoff.
    SMA SB 3000, old BP panels.
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #37
    Re: Buying new equipment
    inetdog wrote: »
    Or the plate could be thicker overall for mechanical strength but have a "waffle" surface to expose more area.

    Or it could be a sales pitch. Two batteries with the same weight, but one has all the "good stuff" - thicker plates, more surface area, more electrolyte and the name "RE" on it. Because they know most people won't figure out that they're being fed a line of bovine waste.
    --
    Chris
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  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    #38
    Re: Buying new equipment
    inetdog wrote: »
    Or the plate could be thicker overall for mechanical strength but have a "waffle" surface to expose more area. A spongy surface, as used in a cranking battery, will give an enormous amount of surface area, but the texture will fill in as it goes through discharge/charge cycles.

    On this side of the pond the differences between a traction battery and stationary battery (used for RE) are primarily that the stationaries have lower SG electrolyte (1.24), they're made from a stronger case material so that each 2V cell is self supporting, they're usually transparent to check levels easier and have much more spare room above the plates, which means you only need to fill them once a year or so.

    Most batts here have used tubular instead of flat plates since the 1950s. Seems more like a cultural thing, the same way the japanese use AGM and gel for everything and think that flooded batts belong in the stone age ;)
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #39
    Re: Buying new equipment
    stephendv wrote: »
    On this side of the pond the differences between a traction battery and stationary battery (used for RE) are primarily that the stationaries have lower SG electrolyte (1.24)

    The technology in lead-acid batteries, and they way they work, hasn't changed in the last 100 years. They already knew 50 years ago how to make batteries that will last 20 years or more. So basically, when Trojan and these other companies come with the "Maxi-this" and "Ultra-that", and whatever, it's all snake oil. Sales pitch.

    They make heavy duty industrial batteries that last longer and that are expensive, and they make light duty ones that are less expensive. And that hasn't changed in the last 100 years either.
    --
    Chris
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  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    #40
    Re: Buying new equipment
    ChrisOlson wrote: »
    So basically, when Trojan and these other companies come with the "Maxi-this" and "Ultra-that", and whatever, it's all snake oil. Sales pitch.

    Sure. My point was that if you wanted to buy a good quality batt, you should look for specific characteristics and then you can ignore all the marketing hype. E.g. first look for the published cycle life according to IEC 61427, then look for a heavy dry weight, low SG and low antimony content.
    Once you've found a good battery based on those criteria then you can look for the "nice to haves": 2V self-supporting cells, transparent case, lots of spare electrolyte above the plates, etc.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #41
    Re: Buying new equipment

    And good luck finding that information from your average battery retailer. :roll:
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  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    #42
    Re: Buying new equipment
    stephendv wrote: »
    E.g. first look for the published cycle life according to IEC 61427, then look for a heavy dry weight, low SG and low antimony content.

    That is exactly what I did when choosing my batteries. And I have chosen Trojan Industrial IND. I would've chosen Surrettes, but they had a very bad Peurket number.

    They know that people look at the published characteristics. Therefore they do not really care about characteristecs that are not published. When I got my batteries, I found out that to function normally they need extraordinalry long absorption times which are impossible to accomplish in any real-world sitution. Absorption times are not published anywhere, so they don't care.

    To be able to charge batteries in a reasonable time (which is still on the long side), I had to dramatically increase charging voltages. Now, the published cycle life, measured at their recommended charging voltages, goes down the drain, and might be dramatically shortened. Because of higher voltages the efficiency figures go down compare to published numbers. And maintenance cost goes way up. Should I known that, I would never think of buying these batteries.

    What you don't know will hurt you.
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #43
    Re: Buying new equipment
    Cariboocoot wrote: »
    And good luck finding that information from your average battery retailer. :roll:

    The people that I've talked to that handle forklift batteries usually don't beat around the bush or come up with all sorts of Fancy Talk. Like GB Industrial for instance - they basically guarantee the battery will have 80% of it's rated capacity yet after five years based on 1500 cycles to 80% DoD.

    If a new GB battery becomes unserviceable due to defective workmanship or material within 84 months from date of shipment, it will be repaired or replaced at Giant Battery Co.’s option. There will be no cost for parts or labor, F.O.B. the nearest GB service location for the first 60 months. Parts are covered, pro-rated, for the remaining 24 months. Repairs will be made by a GB servicing agent in the area or a pre-approved battery repair center. If the battery is to be replaced, it will be replaced with a battery of comparable size and type.

    Even on reconditioned batteries they provide a one year unconditional warranty and provide a tag with all the test results of how the reconditioned battery tested out on a load bank after it was put back together.

    They even tell you exactly how one is built, without the Mumbo Jumbo you get from Trojan, et al.
    http://gbindustrialbattery.com/BatteryConstruction.html

    There's real batteries and then there's toy batteries. I've noticed that the toy ones seem to involve a lot of "Black Magic" (or so they'd like you to believe).
    --
    Chris
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  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    #44
    Re: Buying new equipment
    ChrisOlson wrote: »
    Like GB Industrial for instance - they basically guarantee the battery will have 80% of it's rated capacity yet after five years based on 1500 cycles to 80% DoD.

    If you read the FAQ section of GB Industrial you will find this:
    Industrial batteries are typically designed to last at least 1,500 charge cycles, over a five to fifteen year period. Each time you charge a battery, regardless of how long, it constitutes one cycle.

    Consistently charging a battery twice per day, during lunch breaks for example, is known as Opportunity Charging, and reduces the useful life of a battery by 50%.

    Routinely charging the battery before it is 80% discharged is another common form of over charging. For example, if you only use the battery a few hours a day, it’s best to use it until it is truly in need of charging before actually plugging it in. Remember, each charge constitutes one cycle, so try not to charge unnecessarily.

    I'm sure these batteries are as well built as any, but the above quote would seem to say that these batteries are not suitable for an RE environment. I could see them not honoring their warranty based on your 'multiple partial charge cycles per day' usage. I'm not saying that they would void their warranty, just that their warranty is not for a typical RE usage pattern.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
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  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    #45
    Re: Buying new equipment
    ChrisOlson wrote: »
    Our shore power charger is a PowerTech IUIa charger. It runs off either 240V shore power or our onboard Yanmar diesel generator. Interstate told me to set the bulk/acceptance rate at 90 amps @ 28.8, absorb at 31.0 for 3 hours, and finish at 31.2.

    I looked at the Hawker site for info on the powertech charger.... the info was pretty thin ... couldn't even find a spec for current or wattage. I presume that the charging parameters are adjustable to Interstate's specs?

    BTW, if you were to use Interstate L16s with RE equipment (or perhaps you wouldn't use them in that way) what charging parameters would you use?

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #46
    Re: Buying new equipment
    vtmaps wrote: »
    BTW, if you were to use Interstate L16s with RE equipment (or perhaps you wouldn't use them in that way) what charging parameters would you use?

    I think I would set absorb to 31.0 for three hours and then check the SG when they got done to see what it did. With no finish stage in RE equipment I'd probably call Interstate though and see what they recommend on that.

    On the issue with how often you charge a battery, the forklift batteries aren't any different than any other battery. Surrette told me that two years ago. Charging the battery up every day and absorbing it is not good for it and wears it out. That's why I have gone to great pains to design our system with aux loads and gen/load support to adjust loading, to work our bank from 50-80% SOC for days on end. It's more efficient and doesn't cycle the battery every day.

    I know that nobody from the usual train of thought on "how it's done" is going to agree with that, because most people think that shallow cycling is the best. But the deal is, I was told what to do by a guy that's been working with traction/deep cycle batteries for 25 years. I've already seen people doing it the "traditional" way have battery failures long before their time - and not just one and there - lots of them. After over two years of doing it "my way" I've found the batteries are perfectly happy with it, while I've been told by the "traditional" crowd that my batteries would be shot already if I did that.
    --
    Chris
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  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    #47
    Re: Buying new equipment
    ChrisOlson wrote: »
    That's why I have gone to great pains to design our system with aux loads and gen/load support to adjust loading, to work our bank from 50-80% SOC for days on end. It's more efficient and doesn't cycle the battery every day.

    How does this work exactly? Do you not charge at all on most days, or do you just charge a bit to keep it in the 50-80% range? From what the GB industrial FAQ says, they imply that any charge counts as a cycle, is this what you're trying to avoid, or do you just try to avoid charging to above 80% SoC on most days?

    I've got my system setup to float charge for 3-4 days straight and only do a full absorb every 4th day or so. This would prevent overcharging, but if I understand GB correctly each float charge would still count as a charge cycle even though they only reach about 90% SoC during float charging.

    EDIT: Guess what I want to know is why do GB say that opportunity charging reduces battery life. Is it because any charge, even if it's from 50% to 80% SoC is bad, or is it because doing a full complete charge before the battery has been completely discharged is bad?
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #48
    Re: Buying new equipment
    stephendv wrote: »
    EDIT: Guess what I want to know is why do GB say that opportunity charging reduces battery life. Is it because any charge, even if it's from 50% to 80% SoC is bad, or is it because doing a full complete charge before the battery has been completely discharged is bad?

    I was told that a complete charging cycle is bad because every time you do it it sheds some lead off the plates.

    The Classic controllers have a thing in them called "Waste Not Hi". It has a voltage offset adjustment, which I set fairly low (-3.0) that starts loading the system at 3 volts below charge stage with PWM driving AC SSR's. Unless we got exceptional solar and wind power, it prevents the batteries from ever reaching charge stage voltage by stacking on more load until all the RE power is used up in loads.

    I have done the same thing with gen/load support and the gen start/stop triggers in the XW-AGS. Never absorb the batteries with the generator and use the Stop V trigger to stop it if it starts because of voltage sag from a big load on the inverter.

    What it does is gradually discharge the batteries over a long period of time because they don't get to absorb stage. It takes a really good, perfect power day to make the absorb happen. And over time I've found we get one of those about 7-10 days on average (maybe 3 times per month). And there are times when we get several nice days in a row and the bank will get "caught up" and float for a couple days when the wind blows hard.

    But the main thing that has make it adjustable is the Classic and that Waste Not thing they got in there. We heat all our water with electric power and you can soak up a lot of power with Domestic Water Heaters and store that power as hot water. Where the gen/load support comes in is in reducing the load on the battery bank during extremely heavy draws to keep it from cycling too deep and needing a recharge too often.

    I have fiddled with this for years. But not until I got the Classic controllers was I able to "tune" it so precisely as I got it today. And I do change the voltage offset in the Classics depending on time of year and how much power we can make from RE. In the winter time I'll use less offset because we use more power so I need more going to the batteries to control how fast they discharge over a week's time. In the summer I'll use more offset because we get more solar power, and solar power is better at providing a steady charging source than wind is. So I need to send more to loads to keep the batteries out of absorb stage. We added more solar recently, but we're going to use that up in the summer with our new AC unit we put in.

    We got one of those little MidNite Battery Capacity Meters on the wall in the kitchen. The most useful feature on that meter is the three LED's on the left that show when the bank was last fully charged. I don't worry about it until that LED goes from green to yellow, meaning it's been a week since the bank was absorbed. Then I'll start watching it closer to see what's going to happen because if the system doesn't turn that LED green in the next three days or so I'll take some corrective action like shutting off the AUX load on one Classic so the loads aren't taking so much power and the system can catch the bank up and turn it green again.

    It's not one of those things you can do where one fits all. I have even swapped out elements in the two water heaters to adjust the load to what I want to achieve it. And like I said, most people are going to go, "you're going to wreck your batteries". But two years and two months into our new bank, they're perfectly fine with it. I got a carbon pile load tester and I individually test each one every 3-4 months to check to see how their rated capacity is being affected over time. Just got done testing them at two years and every single one tests with new spec on capacity yet at the 20hr rate. Now that I'm satisfied with it I'm going to cut the load testing to every six months because it's time consuming with 24 batteries.
    --
    Chris
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  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    #49
    Re: Buying new equipment
    ChrisOlson wrote: »
    It has a voltage offset adjustment, which I set fairly low (-3.0) that starts loading the system at 3 volts below charge stage with PWM driving AC SSR's. Unless we got exceptional solar and wind power, it prevents the batteries from ever reaching charge stage voltage by stacking on more load until all the RE power is used up in loads.

    Thanks for the detailed reply :) Ok, so if absorb is at 57.6V (as an example, I know yours is higher), then you would apply a charge voltage of 54.6V to the batteries and the excess would go to loads. So you're also essentially applying a float charge except you're diverting the excess power instead of telling the controller to go to float, right?
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #50
    Re: Buying new equipment

    Well, kind of. That Waste Not thing starts applying power to the aux load based on charge stage and the voltage offset, so it works in both absorb and float. Without that it don't work very good and I've tried everything in the past. As the batteries come up to absorb voltage the Waste Not starts tickling the load at 3 volts below charge stage. The more power the RE makes, the harder the Waste Not drives the load. It will only make it to charge stage if the RE produces enough power to power the load, plus meet the battery requirements.

    And there's some days that it does, and it actually absorbs the batteries. But it has taken some "tuning" of the size of the loads to make it work. I like water heating because I can swap out a water heater element for only a few bucks (<$15) with one with a different wattage rating if I need to "tune" it.

    The nice thing for us is that we never run out of hot water anymore. And on a good day I can heat 110 gallons up to 160°F and that will last us 4-5 days if we get a stretch of bad weather where we can't heat water. One kWh will heat 5 gallons from well temp to 130 degrees. And electric water heating is almost 100% efficient at the element. But you can use a LOT power heating water with two 55 gallon water heaters in series :D

    It is not a thing where it will work for every installation. I have played with it for years. I gave up on using DC power long ago because I could never get any hot water out of it with low voltage DC power. If you can't send 2 kW to the water heaters you may as well not mess with it if you want hot water. And 2 kW @ 48V nominal is a whopping 42 amps. With 240V AC power it's only 8 amps. I like to heat water, not wires :D
    --
    Chris
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  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    #51
    Re: Buying new equipment
    vtmaps wrote: »
    If you read the FAQ section of GB Industrial you will find this:
    Consistently charging a battery twice per day, during lunch breaks for example, is known as Opportunity Charging, and reduces the useful life of a battery by 50%.

    I also have read these FAQ sections yesterday and it didn't seem right to me. Just about any manufacturer posts Cycle Life vs Depth of Discharge graphs, which seem to indicate that deeper discharges will give you shorter cycle life. And GB tells us that every cycle is equally bad.

    Then I thought that forklift charger works differently. It keeps the battery under bubbling voltage all the time, but at the end it has constant current phase that elevates voltage quite high, sometimes to 2.75V/Cell or even higher. I think that they believe that this final stage is destructive for the batteries. And if you do it twice a day, it's twice as bad as doing it once a day. Similarly, if you charge only once every three days, or once a week, you avoid these destructive final stages.

    In the RE applications, these final stage is equivalent to absorption. In RE it is done at every convenience, but with much lower voltages to make it less destructive. Unfortunately, this doesn't work with my batteries.

    I looked at what happens to my batteries, and I see that if there are many sunny days in a row, charging current during absorption falls faster and faster. That means that shorter and shorter absorptions are needed, but if I make them shorter, electrolyte doesn't get mixed well anough and SG dwindles lower. However, after one or two cloudy days, everything goes back to "normal". I will be trying to eliminate some of these absorptions during the sunny periods to avoid corrosion. I tried to do that manually and it works fine. The next step is to learn to put XW SCC to float automatically.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #52
    Re: Buying new equipment

    I think Chris' cycling added to what Mr. Surrett told Dave Sparks actually keys together pretty well:
    Dave Sparks wrote: »
    I learned this strategy from Dave Surrette (Rolls) in the late 70's. Pretty much the bible on how I design my systems for off-grid.

    Assume that the system will never reach more than a 90% state of charge.
    Try not to go below 50% SOC, ever! Complete absorption over 90% of the year

    Use the energy stored from 70% to 90% SOC for your daily cycles.
    Save the energy from 50% SOC to 70% SOC for aging to get long battery life.

    I know Surettes has changed their recommendations over the years but I also know they are in the business of selling batteries! If you do the above you will get 10 to 15 years on their batteries with decent maintenance.
    ...

    The part about avoiding 100% charging every day I think is important. That is when heat and gases are generated (and very hard on the battery bank).

    With Chris's profile, it spends much of the time with pure chemical energy transfers from charging to discharging and back (where the batteries are most efficient). And (if I recall correctly) only goes back to >90% charging around weekly +/-. It is different than the get >75% SOC quickly for best life--And I have read several website that suggest that a battery setting below ~75% SOC is hard on it (suflating)--But cycling 50-80% SOC is not.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #53
    Re: Buying new equipment

    I was told to do this by a guy with 25 years experience with traction batteries. That is why I have monitored it so closely. With time I have grown more and more satisfied that it does what he told me it does. The load tests with my carbon pile have been the deciding factor for me in knowing that it is doing nothing bad to the batteries and may prolong their life by not losing capacity so fast with age. Only time will tell. But so far it's looking good because few batteries can still test at 100% of the 20hr rate at 2 years old, and being worked hard every day. That would be like ~750 cycles already on an off-grid system. And I believe I have cut the number of "real cycles" to maybe between 200-250 in that amount of time instead of 750.

    I cannot say enough good things about the Classic controller in being able to do what I wanted. It is the most tunable controller you can buy and has excellent logging so you dump a CSV out of it and graph it to see what it did during the day after making an ajustment. It does a lot more than just charge batteries. I've found the Classic to be a system management tool that does what few controllers can do.

    I think somebody has a really nice off-grid battery bank because they stole the batteries out of a couple locomotives
    http://cjonline.com/news/2013-02-13/thieves-steal-locomotive-batteries-worth-10k-each

    There's a place called Diesel Supply about 40 miles from us that has been a Surrette locomotive battery dealer for over 20 years. I priced some of those 8V deep cycle locomotive batteries and they were $5,700 for each 24V string (at the time) of three batteries for the 820ah ones. I would've needed three strings of them but didn't really feel like parting with that much cash.
    --
    Chris
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