water miser caps/L 16 6v lead acid batteries

Re: water miser caps/L 16 6v lead acid batteries

I cannot think of any reason you are having a problem...

Cells ~1/2 full and still spitting water out?

Have you ever added some sort of battery additives?

Look at the positive terminals very closely... Do they seem to be "pushing up" out of the case? (positive plate corrosion from possible over charging/over equalization/too high of charging voltage)?

Are the sides of the cases "bulging"?

Is there any dark gray/black deposits inside the caps (lead/lead sulfate/lead oxide plugging the caps up)?

-Bill

Re: water miser caps/L 16 6v lead acid batteries

Automated equalization is probably not a good thing...

Short answer, equalize when the cells are out of balance by ~0.030 specific gravity or more. Charge at 15.0 to 15.5 volts or so (12 volt bank) at 5% times the AH rating of the battery bank.

Check the S.G. every 30 to 60 minutes and turn off equalization once the S.G. levels stop climbing.

Roughly equalization should be required~2 months if all is going well.

How often do you have to add water? Typically, you should be adding water to a flooded cell battery bank around every two months. If you are adding more water--possibly overcharging. If you are adding less or almost none--possible undercharging.

Here is the Trojan Battery Manual--Very comprehensive.

Trojan Battery 20 page Maintenance FAQ (PDF).
Trojan Battery Maintenance FAQ in español (PDF).

Equalization is actually very hard on a battery bank and if done too often/too long, can cause internal corrosion and plate erosion.

Also, what kind of charge controller are you using and what are the Absorb Voltage (and time -- if used) and Float settings.

What is your primary charging source (solar panels, how many... Backup charger / genset if used / etc.).

If you are using wind turbine to charge your battery bank--do you have some sort of charge controller setup to manage the wind power (typically a shunt/diversion controller to "bleed off" excess power--Need to keep wind turbine loaded to prevent over-speed).

Are you using a remote battery temperature sensor? Hot batteries need lower charging voltages.

If you have parallel battery banks, take a look at how they are wired in parallel--You want the battery wiring to be "balanced" between banks to ensure that parallel strings are properly sharing discharge/charge currents.

Smart Gauge Battery Wiring

It sounds like there is overcharging going on--but it is not clear yet what is causing the issue.

Deep Cycle Battery FAQ
www.batteryfaq.org

-Bill

Re: water miser caps/L 16 6v lead acid batteries

windysolar wrote: »

A little thanks to everyone for all the input. first upon rereading my manuals after five years i did discover the fellow who sold me the stuff did in fact hook the batteries up improperly. As you mentioned they were hooked to one group of batteries in series and not across the two paralleled banks so they most likely were feeding and charging them at different rates. the hydrometer did not steer me wrong either ,showed me that one bank was almost dead while the other was slightly higher.

Ahh... The old "trust but verify" quote strikes again.

Wow--Went from sounding like an overcharging issue (sputtering vent caps) to serious deficit charging issues.

Good thing you had the discussion and go back to basics (wiring, hydrometer, voltage measurements).

Since your post i have reconnected my batteries in the correct manner across the two paralleled banks and have been charging them up today to see if i can bring all the cells back to the same level. I have also readjusted the charge controller setting and turned off the auto equalization setting.( charge controler is tristar ts-m 45 with digital readout)and have hooked up the the battery sensor feature.

At this point, I don't think auto equalization is causing you problems--unless you are seriously going from 100% state of charge to 20% or less SOC.

But getting control and understanding your system is what is important at this time.

Hopefully my old batteries will rebound now that they are hooked up right! As for a battery temp sensor, no i do not have one. My batteries are stored in a room where the temp stays roughly 60- 65f.

The controller is a good one. Connecting the remote battery voltage wires to the battery bank is a good thing--but probably not causing your current problems.

Did I miss it somewhere? How many watts of solar power do you have and what is the Array Vmp/Imp setup?

Also what is the battery bank voltage (12/24/48 volt)?

The only charge controller i am using for the windmill is the built in internal regulator, is this not a good idea? The windmill is a Air 403, which is currently set to shut down when voltage hits 28.3v. If it is advisable to use an external regulator can a guy purchase one with the built in feature of a diversion regulator as well or does that feature only come as a separate option? And... would it be a good idea to use an identical charge controller as the one i use for my solar panels(ts-m 45 tristar).

Frankly, with the large battery bank and the low state of charge--I would not worry about the Air 403 at all right now. It would not hurt to let the Air 403 charge to 30 volts or more (may be an issue if you have heavy/constant winds)--but lets get the battery back to consistently charge and understand any other PV/Genest issues you may still have.

I assume that the Air 403 is a pretty small part of your overall charging energy.

Do you have a battery monitor or some other way of measuring charging current (charge controller, shunt, DC Current Clamp Meter, etc.)?

So we can figure out how much current (and voltage/power) you should be getting from each of your charging sources and how much they are actually contributing to your overall daily energy harvest.

One more thing i can pass on to you that i did notice was that because the banks had been running at different s.g levels for a while, once i started charging them before i adjusted the cables the other day i had told you that one cell was dropping and one rising,well as i began to charge it happened again, so i adjusted the levels again accordingly, then a while later it happened again, to the battery just ahead of that one in the series, bizarre.

It sounds bizarre--I can understand a bubble of gas generated under a stack of cells--but I would not expect it to be consistent "consumer" of water...

People have filled the batteries (before charging) to the "full line" and then started heavy charging--Batteries gassed, got warm, and electrolyte was pushed out the fill/vent... Normally, before charging, make sure the plates are all covered with electrolyte--Charge, then when 100% full--then add water to 1/2 full or a bit more.

BUT once i connected the batteries properly as mentioned the problem seemed to disappear and has not happened again as of yet so hopefully that could have been part of the problem?????? i hope.

I don't think so--but, I guess, anything is possible.

At this point, you need to understand how much charging current/energy you have available on a daily basis and how may Watt*Hour / Amp*Hours you consume in 24 hours.

Batteries do not like over charging or under charging/over discharging (deficit charging)... You need to try and keep it above 50% state of charge during normal operation and try not to spend to much time (days/weeks/months) below 75% state of charge.

-Bill

Re: water miser caps/L 16 6v lead acid batteries

windysolar wrote: »

1st i have 640watts @ 24volts(22amps at high noon) from solar panels, but i do not have a tracker, my panels are fixed. My battery bank is 24volt (4 six volts in series, paralleled to 4 more) total ah of battery bank is 750 ah storage with inverter set to that amount(batteries are rated at 375 ah 6 volts).

The 22 amps from the 640 watts of panels sounds OK.

Your battery bank charging ratio is roughly:

• 640 watts * 0.77 derating * 1/29 volts charging * 1/750 AH bank = 0.023 or 2.3% rate of charge

You should really think about at least doubling the size of your solar array.

For a battery bank, a good starting rule of thumb is ~5% to 13% rate of charge... And if these are "tall" flooded cell batteries, it would not hurt to aim for at least 10% rate of charge:

• 750 Amp*Hour * 29 volt charging * 0.05 rate of charge * 1/0.77 derating = 1.412 watts of panels
• 750 Amp*Hour * 29 volt charging * 0.10 rate of charge * 1/0.77 derating = 2,824 watts of panels
• 750 Amp*Hour * 29 volt charging * 0.13 rate of charge * 1/0.77 derating = 3,672 watts of panels

Many people thought that if there was not enough power, that adding storage batteries was a good solution...

Turns out that adding more batteries bumps up the amount of solar panels required to keep the battery bank happy--An expensive "fix".

Buy more panels or replace the battery bank early because it never gets fully charged.

I was told by the fellow who set me up that when you have two banks paralleled it doubles the ah storage.

That is correct... Paralleling battery strings add current (or Amp*Hour Capacity).

Connecting batteries in series adds voltage.

I do not have a separate battery monitor other than the one the for panel input. In talking about this i am under the assumption that i should purchase one to run separately?(which would be the most accurate/ cost wise)

I like battery monitors... They do not replace hydrometers and good maintenance checks--But they are very easy to use and if you have a spouse/kids/guests--it is much easier to tell them to "start the generator" if you see the display below 50% capacity and recharge to 80% or more capacity then shut down the generator (plus turn of the extra optional loads).

Some good Battery Monitors (also Victron Energy). The Trimetic is a good price/performance model. The Xantrex and Victron have units have a contact closure you can use for an alarm or to turn off the inverter if the battery is too low.

Read about them and see which will meet your needs.

The one on my charge controller does have digital display of battery voltage and also high and low level history

Helpful--but a battery monitor is about as close as you can get to the equivalent to the "gas gauge for your car's fuel tank".

I have done the calculations for usage and do not exceed my input levels 99% time, and have also set my over discharge protection to 22volts (highest setting)on the 24 volt inverter and for the most part never get that low to set it off.

Earlier post said that the hydrometer showed a pretty dead battery bank...

22 volts with light to no load is pretty close to dead. You don't want to take your battery bank to below ~20% state of charge--you run the risk of "reverse charge" one or more weak cells--which pretty much is instant death.

I even do things in the long cold winter months to conserve even more energy such as limiting microwave and toaster use to bare minimum.

Keep monitoring the battery bank resting voltage / specific gravity / battery monitor readings.

When i rewired my batteries i also changed the input of my windmill which was hooked up to the second bank of batteries which in the manual said that it was better as to not detect other charge sources.

Now i have hooked it up to the same terminals as the inverter and charge controller cables thinking that maybe it was not detecting the other charging from the panels and possibly causing issues.

I am not quite sure I follow you here...

The size of the conductors, their length, the maximum current you draw (toaster/microwave can draw upwards of 80 amps at 24 volts), physical connections, all should be checked.

Since you have a parallel string of batteries, a DC current clamp meter to monitor current sharing would be very useful to make sure everything is working correctly.

If you are good with using an accurate DMM (Digital Multi-Meter)--you can check voltage drop and battery voltages to see if the batteries are charging nicely or not.

I checked my batteries when i arrived home today and noticed that the s.g. of the batteries is starting to rebound slowly. Also notice that i have not had any issues with any of the cells boiling out and filling of the others with that acid(which is relieving).

Numbers (state of charge, specific gravity, etc.).

If you have a genset, you probably want to get the battery bank over 80% state of charge pretty quickly. Spending too much time below 75% state of charge can sulfate the batteries and ruin their capacity (days/weeks/months all cause eventual sulfate hardening).

I hope over the next 2 weeks when i am away for work during the week that the cells s.g. will continue to make a comeback. I hope i have given you all the info you needed, and if not i will provide, and thank you so very much for the help you have been providing.

You really want to keep the battery bank over ~75% state of charge when you are away. Ideally, the battery bank should be at 90% or greater state of charge once or twice a week at a minimum.

Don't do 100% / equalizing charging unless you see the S.G. differing between cells by ~0.030 or more -- Then fully charge the battery bank and equalize until the S.G. no longer rises in every cell.

One thing i might ask is about the diversion style regulators. Do they have to be wired to one specific item or can they be wired to different items through a sub panel for different seasons such as hot water tank or ceiling fans etc?

Diversion controllers are there for safety... Whatever the load(s) is / are, you need to be sure that they are sufficient to use 100% of the wind turbine's output when needed.

At this point, the Air 403 is no doing much.

-Bill

Re: water miser caps/L 16 6v lead acid batteries

You are very welcome WindySolar--We all try to help each other out here.

windysolar wrote: »

In an earlier post i said i had two sharp 170watt panels and two 150 isophoton panels( i said cyocera but was mistaken). Is it ok to have different sized panels as long as they are the same voltage(24v)? If this is ok then when i purchase more i`ll see what is truly best value for the money. Any suggestions on lastest panels?

You are getting a fairly large array going here... I don't remember what solar charge controller you have (PWM/MPPT/etc.).

Mixing and matching panels can be a really big pain in the behind.

Short answer, you can parallel solar panels if their Vmp's match within ~10% or less. More than 10%, and you can loose significant output with the new panel (you won't get 100% sum of the wattage output with large mismatches).

For adding panels in series, you should have Imp matching within 10% or better.

When paralleling panels together (3 or more parallel strings, or 2 strings+ with different rated panels)--There should be series protection fuse in each string--to prevent high current back feeds from the rest of the array flowing into a shorted panel/panel leads. One fuse per parallel string sized from the specifications (typically around 2xIsc or a little less).

Last night after writing my post i went to the link for the online store and was actually reading about some of the battery monitors you mentioned and i did kind of like the xantrex lite version. Does this model have a box for mounting to the wall or is it a separate purchase? I`ll have to contact them and see if they have free shipping to Canada( thinking not though).

I and (and Niel, the other moderator) have no relationship with NAWS other than as volunteer moderators here--So, for details about shipping and options--you will have to give them a call.

I do not remember Xantrex having a surface mounting box option--but I do not know.

Yes and i was hoping to get the generator on the batteries today but she wouldn't go today, guess -41c last night was too much, but it is supposed to be much warmer tomorrow, so i know it`ll start for sure then. As I type this it is only -22c so should be running up tomorrow.

You know, cold weather like that always sounded like fun to me (toss a mug of coffee into the air and ice crystals tinkle down to the ground--so I hear)... But cold weather here for us is just above freezing with a 1/2 inch of ice in the bird bath... I know it is dangerous.

I am thinking that in using the meter on my charge controller alll this time to tell me my state of charge on the batteries is definitely not what I should have been doing, so in short ARGH! tHINKING THAT WHEN THE METER WAS SHOWING 25.4V IT MUST BE FULL WAS WRONG? And i should have had the voltage meter hooked up from the get go as well.

I am not quite sure I understand the question...

Anyway, the meter (volt/amp) on the charge controller can only tell you what the charge controller is outputting. It does not know if the current is going to the battery or the loads, or a combination of both.

The only accurate voltage test for a battery a bank is the Resting Voltage of 12.7 / 25.4 / 50.8 --correcting for bank temperature if not around 25C (after 2-3+ hours of no load/no charging current). Otherwise, battery voltage is not a good estimate of state of charge.

Roughly, is the bank resting voltage is below 11.58 / 23.16 volts or so--That is ~20% state of charge and you should draw no more current as you can permanently damage the battery cells. And you should fire up the generator quickly (within hours, or a day at the most) to prevent the sulfates from hardening (crystallizing).

For the Charge controller, it will read less than ~29 volts when the battery is less than ~80% charged, and once the charger reaches ~29 volts, then the charging current will taper off to near zero.

My dad used to say bone headed always seam to learn things the hard way Eh! lol

Yea, Dad was right--We all learn much more from our mistakes.

I am definitely taking this info to heart and must make a few changes, so i guess it`ll be time to shop for some equipment or as Capt. KIrk would always tell Scotty "we need more power Mr. Scott!" and as he`d always comeback with "I`m doing the best I can Capt" but with your guidance we`ll be back on line in no time hehe
thanks again bill

Who would think that Star Trek 1 quotes would show up on a forum like this. :roll:;)

-Bill

Re: water miser caps/L 16 6v lead acid batteries

WS,

I will try and answer--My battery knowledge is limited.

windysolar wrote: »

...another question i meant to ask the other day was why would my battery posts be pushing up on some of the positive posts if i am underpowered on panel input?

As I understand, positive post "extrusion" is typically the result of positive grid corrosion typically caused by "over charging / over equalization". When you charge a battery at 100% state of charge, the energy is turned into H2 and O2 gasses. The good thing is this mixes up the electrolyte and reduced stratification issues (low density at the top of the cell and high density electrolyte at the bottom). The bad thing is that the O2 forms at the positive plate and causes grid (and probably lead) oxidation--causing the plates to "grow" and put the positive post up and bulge the sides of the case.

Overcharging (or overfilling) was a guess based on your symptoms (electrolyte being forced out of the battery).

But the voltage measurements seem to show under/deficit charging.

It is always possible that you run the battery low most of the time, and put a genset on once a week or once a month and over equalize (equalization should only be ~1/2 hour after the battery bank is full charged and all cells are no longer showing a rising specific gravity).

In your case--I do not know.

Second could it be from years of running at a deficit and build up of harden scale is causing this?

I don't know--I don't think sulfates crystallizing (from long periods below 75% state of charge) cause plate swelling--But I may very well be wrong.

And if this scale is contacting the plates should they be replaced before adding more panels?

I believe the scale is an insulator. It reduces plate surface area, reduces "active plate volume" and reduces free sulfuric acid in the electrolyte (locks sulfur ions in the crystallized lead sulfate). All of this reduces the available storage energy in the battery.

Once the battery looses 20% of its capacity--some vendors call that end of life.

If you never draw more than 50% from your battery bank and don't have high surge currents--You can probably just keep the banks until the no longer store enough power for your needs.

The big thing is that sulfate crystallization and grid/plate corrosion is not reversible. Live with what you have and learn how to reduce the effects on your next bank (typically more solar panels, more generator run-time, and/or less loads).

And one more, if the batteries have sustained permanent damage from this, would a higher voltage show up on the charge controller when batteries are at rest at night with no loads on?

Battery resting voltage (2-3+ hours of no charging/no discharging current) is related to the strength of the electrolyte.

SG versus voltage

Specific gravity = single-cell open-circuit voltage - 0.845 (example: 2.13v – 0.845 = 1.285)
Or
Single-cell open circuit voltage = specific gravity + 0.845.

Of course, you have to take temperature into account as well has have accurate/calibrated volt meter that can read down to 3 decimal places.

Eric/Westbranch posted a link to a 1922 battery repair manual. A very interesting read and look back almost 90 years at technology and mass production (near the end are some factory photographs).

Antique battery info (1922) (thread)

And here is the direct link to the table of contents:

THE AUTOMOBILE STORAGE BATTERY ITS CARE AND REPAIR

And this is a pretty complete manual from a battery manufacturer that lists good practices:

Trojan Battery 20 page Maintenance FAQ (PDF).
Trojan Battery Maintenance FAQ in español (PDF).

As RC says,

RCinFLA wrote: »

There are two opposing curves associated with float voltage for positive plate and negative plate.

The float point is in the compromise 'well' of the two curves. This point changes with temperature of battery.

Negative plates like higher float voltage to keep them from sulfating.
Positive plates like lower float voltage to keep them from corroding and excessive lead oxide build up.

I like Dave Sparks' post:

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 OP is making it complicated by mixing battery types and not really stating a lot of information that would allow decent specific advice.

Oh yea, I am really happy that Surrette and Trojan are making L16's with 1000 AH capacities @20HR. Been bugging them for many moons to do batteries less than 125LB's!

Dave has been doing Off-Grid for many years and making a good living helping others go off grid--I do not have that experience.

-Bill