Off Grid Home › Forums › Technical Discussion › additives or gadgets to fix or renew batteries
- This topic has 45 replies, 8 voices, and was last updated 11 years, 4 months ago by retired profile of WrethaOffGrid.
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June 12, 2013 at 12:00 AM #6756512vmanParticipant
“I have been very hard on my deep cycle batteries, the ones I have are not that old, just a couple of years old, but are not holding a charge very well, I’m bad about not equalizing them because my inverter will not work while the batteries are being equalized and I live off of my batteries, I refuse to equalize them while I’m not home, I don’t want to risk overheating or boiling out my batteries.”
I ruined a set of batteries in the early years by draining them too much over and over again. I didn’t get 2 yrs. out of them. (4 Golf Cart Batteries, Series – Paralleled for 12 v.d.c.) Sometimes I’d let the voltage drop to 10-11 volts before I started shutting things down. That was a huge mistake! You should never take a 12 volt battery below 11.9 volts UNDER LOAD, meaning do the voltage test when you have things running. An unloaded battery will show a higher voltage than the real capacity. They show their real color under load, hence, load test..
Most inverters will shut down when the battery voltage drops to 10.5 volts “Under Load”. If your inverter shuts down, you seriously discharged your battery way too low. It doesn’t take many cycles like this to damage a battery, believe me..
If your inverter won’t operate during a charge period, you have your bulk charge voltage set too high. Most inverters will operate to a voltage of ~14.5-14.8 volts before the over voltage sense shuts it down. If your bulk voltage is going higher than ~14.2-14.4 volts, all you are doing is boiling the life out of them. That isn’t good either. If you need to add water more than once a month, you have your bulk voltage set too high. It can take a week of sunny days to get the settings adjusted correctly but it’s a must. You can’t guess..
June 12, 2013 at 12:00 AM #67566retired profile of WrethaOffGridSpectatorThanks 12vman, experience is what I was hoping to find. I’ll check what I set for the bulk charge, I did it some 5 years ago, my memory isn’t that good :) Might just have to bump it up a bit, or down depending on what it’s set on. I don’t have to add water often, in fact very rarely.
The desulfation unit you use, it says it can be hooked up to up to 3 12v batteries, what is your setup? Do you use one or more of these units or does one handle all of your batteries?
Are you also on the 12vDC Yahoo group?
Wretha
June 12, 2013 at 12:00 AM #6756812vmanParticipantYep.. I’m a member over there but I pick up too much crap on my computer going to Yahoo so I rarely go there anymore..
I had my desulfation unit connected to 4 – 6 volt golf cart batteries and it did a wonderful job, I believe. Now I have 8 – Rolls Surrette S-600 batteries configured at 12 v.d.c. https://www.dcbattery.com/rollssurrette_s600.html I have the desulfation unit connected to these but it may not be enough. I ponder another one or two..
https://imageshack.us/a/img809/2968/chicksandbatteries014.jpg
June 12, 2013 at 12:00 AM #67569retired profile of WrethaOffGridSpectatorSorry 12vman, I don’t know why but this forum/site picks out posts, seemingly at random to moderate, I will see them and approve them assuming they aren’t spam… I wish I could change how that works, I don’t see a way to change it from my end, I’m a moderator, believe me I have looked! If you post a message and it doesn’t appear right away, just be patient, I’ll see it and approve it, it might be the following day, but it will be seen. If one slips by and doesn’t get approved, you can always email me directly and let me know about it
wretha(at)gmail(dot)com
Wretha
June 12, 2013 at 12:00 AM #6757312vmanParticipantThanks Wretha. You can clean up this thread if you’d like. #46270 was my original response. I’m a mod at a couple of sites myself so Thank You and I feel for you.. LOL..
June 12, 2013 at 12:00 AM #67576caverdudeParticipantIf you keep a battery topped off for a month or two before you use it, such as a trolling motor battery, which frequently doesn’t get used for long periods of time, will this stratification occur? I mean the battery will be staying 95 to 99% charge for long periods.
June 12, 2013 at 12:00 AM #6758212vmanParticipant“If you keep a battery topped off for a month or two before you use it, such as a trolling motor battery, which frequently doesn’t get used for long periods of time, will this stratification occur? I mean the battery will be staying 95 to 99% charge for long periods.”
Short answer.. Yes..
The internal resistance of the battery stays high because it’s not being discharged and it doesn’t draw much current. This allows the voltage to rise to the float voltage level of the charger easily and quickly, which doesn’t create many bubbles. The bubbles is what mixes the electrolyte..
Most float chargers (A.C. Type) only allow the charge voltage to go maybe to ~ 13.2-13.4 volts max so the battery doesn’t boil to death. Hence, no mixing..
June 19, 2013 at 12:00 AM #67612MrEnergyParticipant20 years of study and experimentation with battery recovery circuits shows they work, but usually they take weeks or months to fully recover the capacity of a deep cycle battery. I have technology I developed personally that does this in a matter of days using a low frequency pulsing scheme. The only electronic devices that do work are capacitive discharge, or inductive/capacitive discharge. These are large unit the size of a shoe box. The very small ones the size of a cigarette box are inductive/capacitive using an old 1990’s circuit I will post for you if you like and they take many months to recover T105 or L16 sized Trojans.
The additives are epsom salts, Tetrasodium EDTA, Cadmium Sulphate, and sodium hydroxide (Lye). Some of these additives begin to reverse sulphation, but end up falling short in most cases. The only way I have found to work 100 percent of the time is to drain the old electrolyte from the battery, put fresh distilled water back in, and mix TetrasodiumEDTA into the distilled water. I then pulse the battery for 24 hours or until bubbling stops. This eliminates all lead sulphate from the plates and brings the battery back to new capacity. The old method is to use Sodium hydroxide in distilled water, let it sit overnight, then drain and flush with distilled, then install new electrolyte (8:1 water to 99 percent sulfuric acid concentrate). The problem with the old method is you end up with lead plumbates which need to be mixed into concrete or something to lock them into a matrix so they cannot leach into the soil and contaminate aquafers.
Hope that helps,
Tad
There are other methods we can discuss, some effective, some not so much.
June 19, 2013 at 12:00 AM #67615retired profile of WrethaOffGridSpectatorThanks for the info MrEnergy, do you market your gadgets that works in a few days? If so, please give me some details, do you have a website, videos or such?
Wretha
June 19, 2013 at 12:00 AM #67625MrEnergyParticipantHi Wretha,
All of my designs are open source in hopes of helping people with these issues and making life easier for people who are trying to do the right thing environmentally. I will be selling units at the end of the summer that are microcontroller controlled so they will be fully automated both at charging and discharging. I also plan on giving full multi-week E-classes on real-world off-grid systems which will include advanced electronics for building ultra efficient sine wave inverters (identacle to the Outback, Xantrex, Magnum, etc pure sine inverters), high frequency DC-DC converters (I.E. Flexmax 80 type of charge controllers), Tracking controllers, pulse recovery systems for “dead” off-grid batteries. Building heating systems such as concentrated solar heliostats and using Organic Rakine cycle (ORC) for driving turbines for power generation while heating and or cooling homes. Also there will be in depth information on water recycling through both aquaponics, solar steam distillation, and how to replace the base minerals and PH of water in such systems. If I have not built and used the technology here at our home, I won’t be going into it deeply in the classes. This is all hands on, practical, build it yourself type of information on fairly advanced and critical power systems used to keep a family totally self sufficient in all aspects of power, water and food.
Most of the above used to be tightly held trade secrets, but I have a feeling people may need this information and skills in the coming years to make it easier to deal with possible changes to our way of life.
In the meantime, the simplest way to build an electronic battery pulse recovery system is to use a 555 timer, or micro-controller. You need to set the PWM frequency at 30-60Hz and it will be driving a very low RDS-ON mosfet rated in the 75 Volt @ 100 ampere range (IRF 2805 is fine). The power supply can be anything in the 20-30VDC range, even a solar panel. The power is regulated by a high voltage regulator capable of 50VDC or so (which are now very common). You could also use an AC source at 120 VAC, then use a step down transformer to go from 120VAC to 30VAC, then rectify to DC and charge the cap directly from this source. The capacitor is sized at around 10,000 to 50,000Uf. Each pulsed to the gate of the mosfet releases an entire capacitor charge into the battery and thus “chips away” at hard sulfation layers on the battery plates, without heating or substantially boiling the electrolyte. The pulse width (duty cycle) only needs to be about 2 to 5 milliseconds in width as we are giving the battery a long rest period after each intense pulse from the capacitor discharge. This eliminates heating of the battery, and yet the voltage is low enough that is does not shed any lead from the plates. This really performs an equalization charge, but at a slower, and more controlled rate, and without damaging the battery in any way. The cables from the unit need to be in the 4 gauge or larger size in order to transfer maximum energy to the battery. High quality industrial battery cables can be used, or you can use fine stranded welding wire. There will be a small amount of inductive ringing in each pulse because of the cables, but not enough to worry about.
The more advanced units I am building test the batteries internal resistance by sending a single pulse out, and then counting how long it takes for each pulse to be absorbed. Since we can use RC time constant, we know exactly what the internal resistance is. We can then tailor our frequency and duty cycle to that specific battery, even as it changes while charging. We also superimpose higher frequencies on top of the base waveform which greatly increases the speed of the recovery of the battery. We then log the internal resistance and other parameters to an SDcard in the form of a text file so we have a log of how bad the battery was when we started and what happened as we progressed through the process. This allows one to make a spread sheet with charts to see how the process went. It also allows for immediate revealing of shorted cells (mechanically damaged cells).
Once a full cycle is done and the battery is topped out at 15.5VDC, 32VDC, etc (equalization voltage), we then intentionally discharge the battery at a 20 hour rate down to 5 percent or less charge capacity, then we repeat the process. This eliminates the hard sulfation layers that other electronic methods cannot touch. Each full charge/discharge cycle that is performed typically recovers about 40 to 80 percent of the capacity of the battery. The first cycle can take anywhere from 2 days to over a week depending on how thick the sulfation layers are. But once at least 2 to 5 full cycles have been performed, the battery is at factory or better rating.
Anyone with basic electronics knowledge can build this unit for you.
Sorry for the long winded response = )
Tad
June 19, 2013 at 12:00 AM #67627retired profile of WrethaOffGridSpectatorWow, that sure is a mouthful :) Thanks for your detailed answer, I am familiar with some of the components you speak of, I have a friend who is a tinkerer, unfortunately he lives about 500 miles from me…
Be sure to let us know (here) when you are ready to start selling your product, if it is as good as you say it is then I’m sure there are people here who would be interested, I know I would. Keep posting here so everyone will become more familiar with you so it will not look like spam when you do announce your product.
You sound like you have a lot of experience with the off-grid life, tell me more about what you do… do you live off-grid or just go around helping those who do (with their electronics) :)
Wretha
June 20, 2013 at 12:00 AM #67631AnonymousInactivesweet toy there dude, i think i want one :)
June 20, 2013 at 12:00 AM #67636MrEnergyParticipantThanks for the comments. We’ve lived off-grid for 8 years. I was designing electronics for lighting control and phase control of AC appliances in San Diego. About 20 years ago I got interested in solar and windpower electronics and started learning about commercial systems. I ended up studying nightly for about ten years before building simple shunt controllers and wind turbines using Hugh Piggots axial flux design. I met my wife 8 years ago and we both wanted to get back out into the country, so we sold everything and moved into the White Mountains of Arizona, about 4 hours drive northeast of Phoenix (we live about ten miles outside Show Low, Az.).
Now, since I had studied and built off-grid electronics I thought I had it all together (lol). We moved up here and found out that all the technical data in the world does not help in real world scenarios of living off-grid. In fact, alot of it was just downright wrong. For instance, how big your battery bank needed to be. I had always calculated that 300 watts continuous draw would only require 1000 amp/hour of batteries and give us a couple days of no sun/no wind without any problems. Well, this didn’t take into account the up to 50 percent loss in capacity when the batteries got below 40 degrees Fahrenheit. Now I find people out here (we are all off-grid in this area) who have been told by the solar store that all they need is 8 Trojan T105’s to run a 2400 sq foot house! And they only need 800 watts of solar! Lol!
End result is that they are always running a generator to charge the batteries just as the sun goes down. When they hit a cloudy day or worse yet snowy day, their batteries last a few hours before the inverter low voltage cutoff takes effect and they are out of power. They then go out and fire up the generator. They spend roughly $200 to $400 per month in fuel and end up spewing out more hydrocarbons than someone grid-tied does, even though they are only using a tenth of the power of the grid-tied household.
At that point I decided to focus most of my time into teaching people the proper way to build a reliable system that they would not have to do anything with but check battery water levels and never have to run the generator (as it should be).
So I spent the next 8 years up here working up the most hassle free and most practical ways of running a house off-grid and also dealing with heating issues when it’s 5 below zero outside without using propane or kerosene. It’s been a real learning experience. Water has been another issue. Most people up here are hauling water in 275 gallon cubes, most of which ends up down the toilet. I figured there was a better way to do it, so I started working on water recycling systems for graywater which would be used a second time for flushing the toilet. I have also found concentrated solar to be very useful in recycling water and making power at the same time, while heating through radiant floor heating.
For a living I work on electronic systems for the new electric cars that are coming out now using the solid lithium polymer batteries. Regenerative braking systems, and charging systems. Our partner is Caleb technologies which will be supplying the new electric cars with their batteries. We are hoping to have cars that get more into the 300 mile per charge range shortly by using better designs for regenerative braking and motor power control systems. If you are interested in seeing some of these things, I do a video update a couple times a month showing what I am working on and how it is progressing. I will post a link to them as I upload them.
Anyways, that’s my story = )
Tad
November 28, 2013 at 12:00 AM #67971retired profile of WrethaOffGridSpectatorI was able to get 2 of the WizBang battery desulfator units, I am testing now as I type, I started the first part of the review here
https://offgriddev.wpengine.com/2013/11/20/battery-desulfator-review/I hope in the following weeks I will see a difference in my batteries. I will keep everyone updated on how things are working.
One thing I noticed right away is the buzz they make, fortunately the one closest to our living area isn’t as loud as the one out on the back deck, I plan on swapping them at some point to see if they are the same in volume or not…
Wretha
November 28, 2013 at 12:00 AM #67972retired profile of WrethaOffGridSpectatorMrEnergy, any progress on your inventions??? Inquiring minds wish to know :)
Wretha
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