Batteries

[Leondk]

Good afternoon

I see on the forum people are negative about silver calcium batteries. I am new to power storage so just some advice.  what is wrong with them? I am looking at Bosch silver calcium because of the price.  R1650 vs R3000 for gel.  what would be the disadvantages of them?

 

 

[___]

17 minutes ago, Leondk said:

what would be the disadvantages of them?

They are brilliant in cars, in my experience. They might even be okay for camping and or your weekend off-grid place. But basically, the trouble is they have short(er) cycle lifes (maybe 500-700), and at least one forum member came back after a few days to find that one of his batteries had gone into thermal runaway while he was gone... and thankfully didn't burn the house down.

[Leondk]

would they still give you the 50% discharge like deep cycle batteries? so the 105ah should get me 52.5ah before they are completely discharged?

[___]

2 minutes ago, Leondk said:

would they still give you the 50% discharge like deep cycle batteries? so the 105ah should get me 52.5ah before they are completely discharged?

Oh they will give you 100%! They just won't do it that many times :-)

They will behave exactly like deep cycles (or mostly), they just won't last as long. @KLEVA is the guy to ask, he has some experience with these batteries.

What happens to a battery, really, is it deteriorates slowly. So the first few times you get 100% of the capacity, then 99%, and so it goes down. So when people say the battery will only last 300 cycles to 80%, they don't mean the battery will be useless at that point. They mean that the battery will have less than 80%  of its original capacity left so that it will no longer be able to cycle to 80% DoD (of the original capacity), it will go dead before that. So if you need 80% of the battery capacity to get through the night (for example), the cycle life tells you roughly how many days it will take before you can't get through the night anymore.

[Leondk]

What would be the best batteries for me to buy then? I have a Axpert 24v inverter ( don't know if the inverter/charger makes a difference in battery choice)  

[___]

It really depends. As I said elsewhere -- and I hope my fellow partners in crime will join soon -- for weekend/camping purposes those batteries are probably okay. For daily cycling the best right now is Lithium Ion, but that is going to cost the proverbial two appendages. People around here like the Trojan T105RE, and that would also be my recommendation (4 x 6V 225Ah). The trouble with the Trojan and the Axpert is that the Axpert usually has trouble equalising them, but that is less of an issue with the 24V inverter that allows voltages up to 31V.

But we haven't even looked at loads and consumption and all that stuff... you can't really talk batteries before you did all that math.

Come-on @The Terrible Triplett, this is your domain!

[Leondk]

Lithium Ion is a posibility for me. Do you have a idea what brand will work on the Axpert inverter? 

[Czauto]

Batteries. Mmmmmmm.....
IMHO i think it's good to start off with cheap batteries. Why? Because you're going to be tinkering and playing with your setup in the beginning and surely going to screw up a battery or 2 in the process. Better to f@ck a cheap battery in that case then.
I started off with 4 x 105ah Energizer "deep cycles" October 2016 (6 months ago). I've been tinkering A LOT since my install and guess what, my 1st "deep cycle" (which was actually a high cycle sealed lead acid) battery has seen it's arse. I started noticing high voltage spikes and very short discharge times and decided to test each battery individually. (I haven't invested in a battery balancer yet)
I switched off the grid supply to get some load on the batteries and tested each one's volts. 1st:12.5v, 2nd: 12.48v, 3rd: 12.51 and 4th.......wait for it.......7.3v. basterdo!!
6 months and the first one's gone. At R1౩00 per battery i could afford to replace the damaged one, not the ideal scenario but hey. It buys me some time to save for a proper bank.
If your system is setup 100%, invest in a proper battery (or bank), if not, stay with the cheapies for now. I would sh@t myself if i screwed up (which i admit i did) a R40k battery bank.....
Now to see if i can revive the damaged battery, just to see if i can. Intelligent charger been trying to do magic for 74 hours already now. Not ready for a load test yet.
Oh yes. Invest in a bmv battery monitor and battery balancers. You won't be sorry.....

Sent from my S60 using Tapatalk

[Don]

Lithium batteries are too expensive right now. I would recommend you get some VRLA batteries. Ritar or BSB Sealed Solar batteries, they can take a hammering. They don't need an equalization charge either and just keep going. Axperts can't equalize Trojan batteries in any case, so forget about them. In 2-3 years time, some new technology would probably surpass Lithium Iron, therefore in about 5 years time, you replace what you buy now, with the new technology.  

[Guest]

45 minutes ago, plonkster said:

... this is your domain.

I'm here ...

Equalizing only becomes a need under certain circumstances. Been blown a wee bit out of whack on the forum if you ask me.

And if you need to equalize, usage dictates it, then we must chat about controllers.

Any case, silver calcium, nope. I say get Trojan T105RE's, slightly more expensive than the "deep cycle" nonsense people sell, but if treated right, very good forgiving real batteries, that you could make last 5-10 years depending on how you use them.

There are obviously more types of batteries than T105RE's, but I like them because forklift operators use them all the time, so you get what you pay for if you treat them right, proven fact.

But before we go there. Load and expected run-time, keeping in mind "wants" which are 10 times more expensive than "needs" on batteries and know that "needs" tend to cost a bit ito having to reduce the load on the batteries.

[___]

33 minutes ago, Leondk said:

Lithium Ion is a posibility for me. Do you have a idea what brand will work on the Axpert inverter? 

I tend to agree with @Czauto here. Just go with the ones you have already. You'll replace them in about a year anyway :-)

There are 4 Li-Ion makers I know of.

1. BlueNova (Stellenbosch, but you need to talk to a reseller)

2. FreedomWon (Pretoria I think)

3. LithiumESS (Riebeeck Kasteel area)

4. SolarMD (Milnerton area)

As far as I know only SolarMD integrates with the Axpert, but not with the 24V model (only 48V). The other guys have 24V batteries, but I'm not aware that they integrate with anything other than Victron. The issue with Li-Ion is that it is a lot more sensitive to bad treatment, and because no two cells are ever the same (regardless of chemistry) and because unlike a Lead Acid a fully charged Lithium cell passes very little current, it is very difficult to equalise them or avoid over-discharge of a low cell without a proper BMS (battery management system) and a balancing method. The BMS needs to talk to the inverter/charger(s) so they turn off when either condition is present. So it is not as simple as just buying the batteries and installing them. There is a massive electronic communication layer that needs to be in place.

[Chris Hobson]

I ended up with midrange priced batteries (4 260 Ah batteries for R15k). It is not the same investment as Trojans or Lithium but not batteries totally unsuited to solar either. Cheap batteries I don't think teach one anything other than that cheap batteries fail easily. That lesson has been repeated often enough for me to want to avoid going down the same path.

[Don]

20 hours ago, Chris Hobson said:

I ended up with midrange priced batteries (4 260 Ah batteries for R15k).

I paid just over R40k for 8 x batteries = 500 Ah. I must have bought the wrong batteries. 

Edit: Sorry, I read it wrong. I read it as 4 260 Ah (four thousand two hundred and sixty Ah), and not as 4 x 260 Ah, haha. My mistake. 

[pilotfish]

I am looking for batteries right now and am leaning towards the OPS 260 AGM/Gel from Sinetech.

It seems that the range is about to be re-branded from OPS to OPR, and the 260 is de-rated to 240 (C100). Now that makes sense to me because the OPS range (quoted at C100) currently goes 60, 120, 180, 260... the 80Ah jump from 180-260 always seemed a bit odd to me.

The OPR 240 has a C10 rating of 200Ah and a C100 rating of 240Ah, which actually makes it a 210Ah at C20 as require by the BMV-702.

...just some useless info for those who think they own 260Ah AGM/Gel batteries

[___]

59 minutes ago, pilotfish said:

The OPR 240 has a C10 rating of 200Ah and a C100 rating of 240Ah, which actually makes it a 210Ah at C20 as require by the BMV-702.

A C100 rating is useless in solar applications. It's a marketing trick, make the number sound high.

It's a 200Ah battery for all practical purposes.

[Chris Hobson]

13 hours ago, Don said:

I paid just over R40k for 8 x batteries = 500 Ah. I must have bought the wrong batteries. 

No that was a special offer negotiated by JZ on your behalf. I am quoting prices from mid 2015. Mind you the price you're talking is close to Trojan territory for 16x105 REs

[Czauto]

I was thinking of this when I upgrade.

https://www.olx.co.za/ad/solar-batteries-200ah-12v-gel-deep-cycles-naradas-ID15VcqL.html

I really cannot see myself spending R40k on any batteries when I can spend R16k on 8 of these.......

Except of course if I can upgrade to Lithium Iron or Zinc Bromide, which is highly unlikely. 

[gallderhen]

37 minutes ago, Czauto said:

I was thinking of this when I upgrade.

https://www.olx.co.za/ad/solar-batteries-200ah-12v-gel-deep-cycles-naradas-ID15VcqL.html

I really cannot see myself spending R40k on any batteries when I can spend R16k on 8 of these.......

Except of course if I can upgrade to Lithium Iron or Zinc Bromide, which is highly unlikely. 

You might pay R16k now, but according to Carl's file on the Naradas (http://powerforum.co.za/applications/core/interface/file/attachment.php?id=781) they'll only last you 1500 cycles at 20% DoD (which is about 2.4-2.5 years if you cycle every day), so after 10 years (which is what companies claim a lithium would last you at 100% DoD), you would have spent R64k in the end.

 

-G-

[___]

44 minutes ago, Czauto said:

I really cannot see myself spending R40k on any batteries when I can spend R16k on 8 of these.......

40k will buy you around 4kwh of Lithium Ion...

[pilotfish]

2 hours ago, Czauto said:

I was thinking of this when I upgrade.

https://www.olx.co.za/ad/solar-batteries-200ah-12v-gel-deep-cycles-naradas-ID15VcqL.html

I really cannot see myself spending R40k on any batteries when I can spend R16k on 8 of these.......

Except of course if I can upgrade to Lithium Iron or Zinc Bromide, which is highly unlikely. 

Wow that is an unbelievably good price for a 200Ah AGM/Gel - it is half the price of similar batteries that I am considering! I was wondering if it is worth giving them a go until I read this;

2 hours ago, gallderhen said:

You might pay R16k now, but according to Carl's file on the Naradas (http://powerforum.co.za/applications/core/interface/file/attachment.php?id=781) they'll only last you 1500 cycles at 20% DoD (which is about 2.4-2.5 years if you cycle every day), so after 10 years (which is what companies claim a lithium would last you at 100% DoD), you would have spent R64k in the end.

 

They are clearly a standby battery and not intended for cycling duty, thanks for saving me some cash

[Czauto]

I'm starting to change my perspective on the whole alternative energy thing. Alternative energy is expensive. Storing this energy for night usage is even more expensive. My 105ah bank keeps my basic loads alive for average 4 hours. That's with a average base load of 200W. This is more than enough for backup when there might be an power outage. I might upgrade to a 200Ah or even maybe a 400Ah bank in future, mostly for backup, but with so little outages at the moment I cannot see it worth spending that kind of money.

I made sure that my family changed their usage habits, basically forced them by installing timer switches on things like the dishwasher, washing machine, etc. It now only powers up between 11am and 3pm and not at the same time. This gives them more than enough time to do a cycle on each. If they miss the time window, tough luck. Wait till tomorrow. During the evening I now have only light loads like led tv's, led lights and floodlights, and then the water booster pump. Stove and water heater is LPG and that's a debatable change I did with no regrets. I replaced my first 48kg bottle on Monday after 203 days of usage. That's and average of R5,32/day. Let's remember were 4 in the house (weekends and holidays we are 6)

I also sourced 2 of these Kill-a-Watt meter thingies from Geewiz recently and have been able to change my usage habits quite a lot by just monitoring what appliances use. Stuff like aircons is a no go. If you're cold, get a blanket. If you want to go alternative energy you must learn to distinguish between needs and wants (like other forum members recently also pointed out) I you want to power your want list you're going to pay for it.

To get to the point, I'd rather buy smaller, cheaper batteries and keep them for backup and as a buffer during peaktime loads. I do have Eskom Grid backup so I'm going to use that for nighttime use as long as I can. Guys with an offgrid setup and no choice of Eskom backup, all my sympathy to you. 

And to anyone reading this thats planning alternative energy.......Please read as much on this forum as possible BEFORE you go head over heels into just buying an inverter, a bunch of panels and batteries (like I did). Don't be afraid to ask and learn. Forum members have paid a LOT of school fees by trial and error so learn from each other's mistakes, it WILL save you a LOT money in the long run.

I sure wish I joined this forum BEFORE I sourced my components. I sure as hell would've made some better choices.

[ibiza]

applause to you!!

[Chris Hobson]

21 minutes ago, Czauto said:

Guys with an offgrid setup and no choice of Eskom backup, all my sympathy to you. 

It is a double edged sword for rural folk. Eskom availability charges are so high that going the whole hog makes sense and @PaulF007 strategy of going prepaid on a rural supply gives him the best of both worlds. The advantage for us that we can write our installation off in tax whereas most urban users are using their after-tax income to do solar.

[gallderhen]

1 hour ago, Czauto said:

 

I'm starting to change my perspective on the whole alternative energy thing. Alternative energy is expensive. Storing this energy for night usage is even more expensive.

 

 

40 minutes ago, Chris Hobson said:

It is a double edged sword for rural folk. Eskom availability charges are so high that going the whole hog makes sense and @PaulF007 strategy of going prepaid on a rural supply gives him the best of both worlds. The advantage for us that we can write our installation off in tax whereas most urban users are using their after-tax income to do solar.

 

This is pretty much what it boils down to.

In my opinion there is no real benefit currently to go battery-offgrid in urban areas, if you are trying to save on electricity. In the end you don't save that much and you'd actually save more by changing your usage behaviour and running all of the things that can be run, during the day on solar panels, leaving only the essentials for night-time usage.

 

The only time battery-offgrid will be of benefit in the suburbs, is if you go all-in and plan for the next 30+ years. But that is alot of upfront capital which is out of reach for most people.

 

-G-

[Don]

38 minutes ago, gallderhen said:

In the end you don't save that much and you'd actually save more by changing your usage behaviour and running all of the things that can be run, during the day on solar panels, leaving only the essentials for night-time usage.

That is the way to do it. My wife tried to start the dishwasher only once at 18h00, just as the sun set. I shouted from the study for her to switch it off. She asked me what about the dishes? I told her she can wash them by hand. The dishwasher has been standing idle the whole day while the sun was shining and I had a lot of spare capacity. Tough luck. She now runs the dishwasher early every morning.