Blasphemy..... Solar power.

[BruceM]

Lead acid battery life is seriously shortened in high temperatures, and even more so by charge controllers that aren't battery temperature compensated.  At high temps the battery charge voltages must be lower or positive plates get eaten up. So it's the double whammy if you have both fixed voltage charging and high temps.  Phoenix, AZ has the same problem with very short battery life in cars, due to fixed voltage alternator regulators are the problem there along with seriously elevated temps. The newer cars with always on electronics cam also be battery eaters.

I read that the big name battery companies such as Johnson Controls monitor their lead very carefully.  For positive plates they don't usually use recycled lead because of the antimony.  These are not fly by night companies; they assay their metals.

Modern equipped boats are more likely to destroy batteries than in days past because of the increased electronics power load, and continuous phantom loads from inverter and/or DC-DC converters. Lead acid battery life is also quite limited based on DOD (depth of discharge) or when left slowly discharging for days or weeks, which causes sulfation, loss of capacity and eventually shorted cells.

There may be something to the virgin lead thing-  but I'm especially skeptical of only marketing information with no independent engineering test data.

[starfire]

According to my battery bible,   3rd  edition 1940 written by a George Wood Vinal,  a physicist for the National institute of Standards in th US, the only main problem mentioned with lead impurity leads to "local action" causing faster self discharge.  The actual battery function remains  unaltered. Many "impurities" have been tried over time to enhance certain qualities, especially adhesion to the supporting grids, but the main technical advances have been to  ease and streamline  manufacture.
So, I would think that "virgin lead" is more an advertising ploy rather than a real advance, perusing  battery sites does uncover some rather suspect claims here and there. Battery additive snake oil is still alive and well, despite being firmly debunked in this same book  nearly 80 years ago.
These lead carbon batteries sound interesting.....
heres the link again..... if anyone has knowlege of these....

https://www.hiteksolar.co.nz/products/6v-300ah-lead-carbon-supercapacitor-lcs-pb-c-battery-latest-technology

1500 cycles at 100% Discharge capacity
2400 cycles at 80% Discharge capacity
3000 cycles at 60% Discharge capacity
3600 cycles at 50% Discharge capacity

[mikenash]

Ade FWIW up at my partially-developed, definitely very off-grid property in what is arguably New Zealand's sunniest province I have a "solar shower"

It comprises 50 metres of 20mm black "alkathene" (low density farm water supply piping) wound in a big flat one-layer-thick spiral on a wooden frame covered with a sheet of heavy black plastic 10mm thick that I scavenged off the base of a feed wagon

(sorry I don't have a photo)

Frame is 1600mm X 1400mm and the spiral covers maybe 70% of it.

It's propped up on a stick vaguely north-facing and roughly 15 degrees off vertical

Water from my spring up the hill comes in one end at about 2 bar and the other end uns under the house and is attached to my shower inside

When it has been exposed to direct sunshine for maybe 15 minutes the water is bloody hot - hot enough that you have to add cold water to it at the mixer to have a shower.  There's enough hot water there for a good shower as well as time to wash your hair and a bit of standing-around-wasting-hot-water time as well

It's inefficient in that there is no storage, and in that you need to think about having a shower when the sun shines.  I don't care about those things cos I'm only there for three or four days at a time every few weeks and I have a wetback on the wood-stove anyway.

But it's such a low-tech, low-cost item ($100 for the pipe) and it will produce enough hot water for three or four showers an hour (if you had a queue of grimy folks) that I thought I would mention it.  It has absolutely no moving parts at all unless you count the mixer at the shower

It's the sort of thing that demonstrates how even the crudest "direct" harnessing of the power of the sunshine has so much free energy to give

I once made a more high-tech one with a clear plastic covering and insulation etc - but I made the mistake of leaving it out in the sun with no water in it one day and the "alkathene" promptly melted.  The crude one I now use is so close to idiot-proof as makes no difference

Cheers

[Samo]

Very interesting to read of the setups and opinions...

In my system I have an 86F cap across each battery, while I'm only using 4 x 200Ah batteries, they "should" be taking the brunt of the surge current (washing machine start up etc), being lower internal resistance. Though I've not tried to prove that claim (no time). Each one cost as much as a battery but they do add to the overall current capacity of the system and I'm confident will help extend the life of my AGM batteries. As long as I keep the DOD low, they will give many years of service yet (4 years so far)...

The other technology I'd like to try is the Edison - Nickel Iron battery, no doubt there's some wild claims out there, however the original Edison batteries were very long lived, and while not as efficient or easy to maintain as AGM, an interesting potential option that I'd like to explore non the less...

Samo

[starfire]

Well Glort, me old cobber, you will get a buzz out of this.
It seems these "ultra" batteries linked to  above are an AUSTRALIAN invention.
Bugger me.
And it looks like they are a good thing.... a vastly improved lead acid, same energy density but can withstand far greater DoD without  damage..
Interesting watch for those interested.,, the interweb is wonderful.

https://www.youtube.com/watch?v=N1jusadHkmM

[starfire]

Ummm, us Kiwis are selling them already..... Something else for the Ozzys to get pissy about and insult the Kiwis over! 

https://www.hiteksolar.co.nz/blogs/news/106430214-why-should-i-consider-using-lead-carbon-batteries

[Samo]

Narada sell them here  (oz) too, and for some commentary...

http://forums.whirlpool.net.au/archive/2607369

[BruceM]

The lead -carbon battery was tested by Sandia before 2009.  Note that this is only 10% DOD so not the full story. 
http://www.altdotenergy.com/2009/01/could-lead-carbon-batteries-be-energy-storage-game-changer/

I also found full reports from Sandia.  They did extensive testing of 3-4% carbon added to the negative plate of VRLA (AGM) type batteries and the results were impressive.  They don't sulfate when partially cycled repeatedly, with no "full up" periods to equalize cells.  So carbon doped negative plates in AGM type batteries are the real deal.

It is suspicious that this hasn't progressed further given this rather impressive independent testing. But it is also suspicious that AGM battery prices have continued to be set at more than double that of wet lead given the reduced lead needed for the same capacity. 

[LowGear]

Mr. Starfire,

I get it.

I've popped for two AGM batteries in my life.  Both lasted a good strong 10+ years.  They still penciled out on the high side but it was fun pulling that length of life out of a battery.

Casey

[starfire]

But it is also suspicious that AGM battery prices have continued to be set at more than double that of wet lead given the reduced lead needed for the same capacity. 

Bruce, i suspect battery pricing has nothing to do with manufacturing cost, but Watt hours capacity.... watt they can get away with consumers.
Here is a lead carbon for sale here in NZ

https://www.trademe.co.nz/motors/caravans-motorhomes/parts-accessories/batteries-inverters/auction-1448246050.htm


thats 120 ah 12 volt at $960nz  This price seems excessive for a little added carbon when a normal 115ah 12 volt from the same retail outlet is $305..... or 1/3rd the price

https://www.trademe.co.nz/business-farming-industry/industrial/generators-power-supply/solar/auction-1448245446.htm

The first is rated at the full 120 ah at 100 percent DOD whereas the second is usually expected to supply whatever at around  30 percent DoD normally.

I cannot figure out the chemistry of these, carbon is inert, im thinking its presence is more mechanical, the carbon disrupting and preventing sulphate crystals to  form/link in the negative plates, thereby keeping them in solution.
The supercapacitor reference I think is rubbish.

on a related note....

I have over time, as most of us have, tried the battery revitalisation thing.
I have had good success with this
Short out the faulty battery for several days.
Connect it BACKWARDS to a cheap old school non intelligent charger.
Charge it for a few days at low current, a few amps is fine.
Short the battery again, then charge normally with correct polarity.

The idea of this, sulphation can only occur on the negative plates, reversing polarity causes the sulphates to either dissolve, or drop to the bottom.

[mike90045]

2 topics here

a) don't use poisonous automotive anti-freeze with a domestic water system, if you get a pinhole leak in the heat-ex ......

b) I have been running a large NiFe bank since about 2011 (48v, 800ah, daily cycling about 11Kwh) and will look up the proper KoH /  H2O  mix ratio.  It should improve the voltage fluctuation you see, but NiFe does have a much wider working voltage range than lead-acid

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

[Samo]

Ok Mike,

You have my full attention on this one. I've currently use AGM, but from all the research to date NiFe is the technology I'm keen on. You've had some time with them, and I'd be very interested in your real world appraisal:

Maintenance
Charge/Use cycles
Efficiency
DOD - how far down do you run them?
How easy to live with, what's the up/down of it?

cheers,
Samo

[BruceM]

Hi Mike,  I remember you were initially having some trouble with your charge controller not being able to fully charge the NiFe bank due to the higher voltages needed.  But I guess since NiFe don't really care about that, not suffering from sulfation, it matters little.  I'm also looking forward to your first hand assessment of NiFe.

I like your simple solution for the well pump. I've got the same pump with about 200 feet of head to my gravity feed tank on the hill.  I've getting ready to add some PV and some sort of timer/sun sensor for topping off the tank daily via my new inverter also; I can reprogram my battery bank controller to add some new logic like-  if noon and batteries fully charged, and sun level good...pump water unless batteries come out of float.  Do you have any sun level sensing to keep the pump off on a dark day or do you do that manually?

[mike90045]

NiFe info
my install:
https://www.facebook.com/media/set/?set=a.209715335768594.51674.120212794718849&type=1&l=9747e4dde6

> Maintenance
  lots, every 2 weeks, I add 5 or 6 gallons distilled, 20 gall was too much to do at a time, so I'd shifted the cycles around so I'm only doing a quarter of the bank at any 1 time.

> Charge/Use cycles
 ?? I charge and use them

> Efficiency
  about 60%, that's why they use so much water.

> DOD - how far down do you run them?
 the bank is 40,800 watt hours, (51v [42 cells] * 800Ah). My running voltage at sunrise is about 52v in summer, and 49v winter (longer nights) I figure my nightime consumption runs about 5Kwh. I sized to properly allow for their high internal resistance, and to supply starting surge for deep well pump, so I generally have low voltage droop.  I charge below recommended voltage, because that would fry my inverter.


> How easy to live with, what's the up/down of it?
easy to live with, no winter worries about sulfation, they don't care about partial charge. Edison original pocket construction was quite robust, 100+ year life on calls, but only 5 years on electrolyte. I'm going to have to dump & refill (nasty, messy process) my cells this summer.
my cells came from China

[mike90045]

Bruce - I use a common Intermatic timer for 11am-4pm run window, and manually switch off in poor sun.