sunset1 Posted March 5 Share Posted March 5 My current system 1200kva mecer 12v lifepo4 is too small due to increased loads. Next step up in affordibilty is a 24v system. Read a bit about salt batteries coming to consumer market in next 3-5yrs(could be wrong) Ideally I'd like lifepo4 but consider the salt batteries are coming to market I have been thinking of buying lead acid batteries as they are significantly cheaper. Hopefully by the time they die, salt batteries are on the market and a lot cheaper than lifepo4. Am I wrong here? What are your thoughts? Quote Link to comment Share on other sites More sharing options...
JayMardern Posted March 5 Share Posted March 5 If this is for dealing with load shedding, then I'd advise against it. Lead-Acid isn't suitable for the level of load shedding that we experience in a given year; in my experience it's unlikely that you'd get 3-5 years of lifespan out of them, unfortunately. I carefully ensured my previous sets of Lead-Acids (AGM's) weren't cycled below the recommended 60% SoC (at which level they were rated at 1500 cycles), but still failed to get more than 12 months of usable life out of them. Tried 3 sets of replacements; different brands, costs, etc - but it was a bust every time. I still keep that system as an emergency standby, because that's what it is: emergency standby. The tech is simply not made for the regular cycling that South Africa will subject them to. Wish I had better experience to share - but my vote is that you stick to Lithium since it'll end up cheaper in the long run; even if that 'long run' does end up being only 3-5 years. 45 minutes ago, sunset1 said: My current system 1200kva mecer 12v lifepo4 is too small due to increased loads. Next step up in affordibilty is a 24v system. Read a bit about salt batteries coming to consumer market in next 3-5yrs(could be wrong) Ideally I'd like lifepo4 but consider the salt batteries are coming to market I have been thinking of buying lead acid batteries as they are significantly cheaper. Hopefully by the time they die, salt batteries are on the market and a lot cheaper than lifepo4. Am I wrong here? What are your thoughts? eugenedp and sunset1 1 1 Quote Link to comment Share on other sites More sharing options...
PsyCLown Posted March 5 Share Posted March 5 I would not recommend waiting for the Sodium-ion batteries, go with LiFePO4 for now as 3 to 5 years is still quite a long wait and new products are often priced at a premium price. You can look at replacing your Lithium batteries with Sodium batteries in around 10 years time when you are due for new batteries. By then we'll have a better idea in terms of performance and pricing as well. I feel you'll have wasted a lot of money in the next 3 to 5 years if you buy lead acid batteries. Lithium batteries are not badly priced at the moment. 24v 106ah lithium batteries for around R10k is pretty good I feel and keep in mind you'll be able to get more discharge out of a Lithium battery compared to lead acid (80% DoD vs 50% DoD), you could even push the lithium battery a bit further and it will handle higher current better and obviously take significantly more cycles. (6000 cycles vs around 150 to 250 cycles for lead acid). ibiza, eugenedp, sunset1 and 1 other 3 1 Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted March 5 Share Posted March 5 1 hour ago, sunset1 said: 1200kva mecer you mean 1200VA or 1.2kVA 1 hour ago, sunset1 said: Ideally I'd like lifepo4 but consider the salt batteries are coming to market I have been thinking of buying lead acid batteries as they are significantly cheaper. I would NOT go with Lead Acid anything, they will die before the Sodium Ion batteries come to market and the next problem will be how good will the initial Sodium Ion batteries be, you may as well go for LiFePO4's for now and you should still be able to sell them in 5 years time, since they should still be in good shape and operational by then, else you can look at Aluminum or Aluminium Ion batteries, they should also be with us in the next 3 to 5 years time as well, I'd hope... sunset1 1 Quote Link to comment Share on other sites More sharing options...
sunset1 Posted March 5 Author Share Posted March 5 Appreciate the info. Very helpful Good sense not to buy lead acid if they can't last more than a year or two. Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted March 5 Share Posted March 5 1 hour ago, Kalahari Meerkat said: you mean 1200VA or 1.2kVA I would NOT go with Lead Acid anything, they will die before the Sodium Ion batteries come to market and the next problem will be how good will the initial Sodium Ion batteries be, you may as well go for LiFePO4's for now and you should still be able to sell them in 5 years time, since they should still be in good shape and operational by then, else you can look at Aluminum or Aluminium Ion batteries, they should also be with us in the next 3 to 5 years time as well, I'd hope... Sodiums are already available in the market AFAIK. Comparable capacity but at a higher price than lithium. Not worth waiting for market forces to get the volumes unless you buy a massive bank. sunset1 1 Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted March 5 Share Posted March 5 29 minutes ago, Scorp007 said: Sodiums are already available in the market AFAIK. Comparable capacity but at a higher price than lithium. Last I checked they were still sitting at less than 1000 cycle life and I didn't see any advertised for sale, either way, I suspect it has quite a road to travel still... and just like the Al-Ion boys, they'd like the *LARGE* market, the EV market to be their customer, comparing the home solar+battery market size with the EV market is like comparing a flea with a heard of elephants... Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted March 8 Share Posted March 8 @sunset1 here's another possible (10 years to market) battery option... aqueous metal ion batteries but again a long way to go and not much info, but 85% capacity remaining after 500 cycles, doesn't quite excite me... Quote Link to comment Share on other sites More sharing options...
WannabeSolarSparky Posted March 8 Share Posted March 8 (edited) On 2024/03/05 at 2:56 PM, Kalahari Meerkat said: Last I checked they were still sitting at less than 1000 cycle life and I didn't see any advertised for sale, either way, I suspect it has quite a road to travel still... and just like the Al-Ion boys, they'd like the *LARGE* market, the EV market to be their customer, comparing the home solar+battery market size with the EV market is like comparing a flea with a heard of elephants... Go check Andy's youtube channel he is busy testing sodium batteries https://www.youtube.com/@OffGridGarageAustralia/videos Edited March 8 by WannabeSolarSparky Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted March 8 Share Posted March 8 49 minutes ago, WannabeSolarSparky said: Go check Andy's youtube channel he is busy testing sodium batteries https://www.youtube.com/@OffGridGarageAustralia/videos Another source. @Kalahari Meerkat A number of sellers on Alibaba. sunset1 1 Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted March 8 Share Posted March 8 6 hours ago, WannabeSolarSparky said: Go check Andy's youtube channel he is busy testing sodium batteries Ok, well, no electronics I have would be happy with a more than 2:1 range of Voltage source... 3.95V to 1.5V... and I think, even though it appears you can purchase some (small/low capacity) cells, they are not ready for the market, or the market is not ready for them, take your pick, I'll take another look in another 18 months and look at what they are about by then... and @Scorp007 after you have ordered some and played around with them, let me/us know what you think, are they ready to replace LiFePO4's and at what cost? I suspect not nyet or any time soon, specifically I can not name any inverters that would be happy with the voltage range this chemistry seems to operate under... Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted March 8 Share Posted March 8 2 minutes ago, Kalahari Meerkat said: Ok, well, no electronics I have would be happy with a more than 2:1 range of Voltage source... 3.95V to 1.5V... and I think, even though it appears you can purchase some (small/low capacity) cells, they are not ready for the market, or the market is not ready for them, take your pick, I'll take another look in another 18 months and look at what they are about by then... and @Scorp007 after you have ordered some and played around with them, let me/us know what you think, are they ready to replace LiFePO4's and at what cost? I suspect not nyet or any time soon, specifically I can not name any inverters that would be happy with the voltage range this chemistry seems to operate under... Those that know me well will know I'm not keen on any new tech until proven. I hope I don't need new batteries for quite some time. I have been negative on sodium while many told me how cheap they will be. I merely provided a link from someone who did some research and a test. We cannot always ignore guys like him, Andy, Will etc to provide us with good data. Don't you think if they did come in very cheap that they can be run in a 14 cell version with just a reduced capacity due to a higher cut off than what the battery can handle. This purely to be used on all current inverters. Due to the voltage curve inverters without comms but voltage setting might find them useful. Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted March 8 Share Posted March 8 2 minutes ago, Scorp007 said: Due to the voltage curve inverters without comms but voltage setting might find them useful. Maybe, but all I've seen so far (haven't looked on Alibaba as yet) are 18650 Cells and then they aren't exactly high energy, compared to NMC or LCA 18650's they are less than half the capacity, I didn't see a price for these, but they'd have to come in at less than 30 ZAR per cell (much less, I reckon) before they may become interesting... 4 minutes ago, Scorp007 said: I have been negative on sodium while many told me how cheap they will be. I'm not negative, but I am not seeing anything of real interest as yet either... so, for now, I am aware of it, but heck probably at least another 3 years and maybe even some chemistry tweaks before this lot may become more interesting and have some useful application... Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted March 8 Share Posted March 8 18 minutes ago, Kalahari Meerkat said: Maybe, but all I've seen so far (haven't looked on Alibaba as yet) are 18650 Cells and then they aren't exactly high energy, compared to NMC or LCA 18650's they are less than half the capacity, I didn't see a price for these, but they'd have to come in at less than 30 ZAR per cell (much less, I reckon) before they may become interesting... I'm not negative, but I am not seeing anything of real interest as yet either... so, for now, I am aware of it, but heck probably at least another 3 years and maybe even some chemistry tweaks before this lot may become more interesting and have some useful application... Price change graph as well as number sold. The 1st ones seem to have been shipped the end of Dec. Quote Link to comment Share on other sites More sharing options...
sunset1 Posted March 12 Author Share Posted March 12 Excuse my ignorance on this one but I'm under the impression sodium batteries will jusy need a adjustable bms and a more recent inverter to change shut off battery voltage? Not much down side except for price at this point? Couple years might be worth it no? Quote Link to comment Share on other sites More sharing options...
Bobster. Posted March 12 Share Posted March 12 (edited) My thoughts are that you shouldn't wait. No matter who wins the forthcoming election, load shedding is not going to go away any time soon. My system has been in over 4.5 years now. When I got it the wife thought this was just a midlife crisis sort of thing. Two days later load shedding started up, and we were in the only house in the street that kept the lights on, that had fridges still working etc. She was then very appreciative. Ever since we have had a largely uninterrupted routine in our house. Lights always on. Wifi always on. Beer always cold. Milk never going off. Etc etc. Do it now. Get a 48V system. You will have a much better choice of batteries, and won't have to scale up again in a couple of years time and sell your 24V inverter at a loss. There is always some better kit just over the horizon. If I were to start today, with the benefit of experience and with what I have learned from helpful folks here, I would not go for exactly the same setup I have now. But I would do it, and I am not sorry that I have what I do have. Edited March 12 by Bobster. pytos Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted March 12 Share Posted March 12 2 hours ago, sunset1 said: I'm under the impression sodium batteries will jusy need a adjustable bms and a more recent inverter to change shut off battery voltage? Nope, unless you can point out and inverter that will operate from a battery voltage of, lets say 58.5V all the way down to 30V... (a 15S Sodium cell battery) Yes, one can make it work, but, the steep voltage curve will mean you can maybe use 30% of the batteries capacity with current inverters, then, unless these cells cost way less than a 1/3 of the price of LiFePO4's for the same capacity, they will be more expensive per kWh than LiFePO4's, if cost is not a factor, go for it, but this lot does not seem ready for the market any time soon (next 12 to 24 months at least). And I agree with @Bobster.'s 48V system recommendation, actually 16S, thus 51.2V nominal is my preference... Bobster. and sunset1 2 Quote Link to comment Share on other sites More sharing options...
sunset1 Posted March 12 Author Share Posted March 12 @Kalahari Meerkat thanks I did not know that about inverters. Imagining they too will have to change should sodium come into play. Right now need to find out if the 16s svolt can talk to a luxpower SNA5000. Apparently they not acquainted yet. Quote Link to comment Share on other sites More sharing options...
Kalahari Meerkat Posted March 13 Share Posted March 13 17 hours ago, sunset1 said: Right now need to find out if the 16s svolt can talk to a luxpower SNA5000. Apparently they not acquainted yet. I don't know or have the SVolt, but, I am sure it uses a BMS which isn't produced by them and used by other battery assemblers and it would emulate one of the common protocols, there was no specification initially about BMS to inverter comms, so Pylontech did their thing and a lot of others use the Pylontech protocol, since a fair number of Inverter manufacturers support this. So, I suspect that the SVolt uses Pylontech's protocol as one of possibly more protocol options, the importer should really speak up and make this information available... sunset1 1 Quote Link to comment Share on other sites More sharing options...
Beat Posted March 15 Share Posted March 15 There are multiple speculations about the evolution of batteries, some with weird claims. There is no doubt that there will be improvements in technology and with respect of size and wight, including the claim of being rechargeable in minutes. But lets look into the basic physics. Lets assume an EV battery of 100kWh. To recharge it in 1 hour requires 100kW of power. To recharge it in 6 minutes would require 1000kW = 1MW. Imagine a service station on a motorway with humble 10 charge columns. That would require 10MW installed power, the power requirement of a small town. But lets look into the charge current. 1MW at 800V results in 1250A charging current. Hard to imagine what cable and connector could handle this. If I'm well informed the actual connector standard allows 25 kW. Not to mention the cell current allowance. Steve87 1 Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted March 15 Share Posted March 15 3 hours ago, Beat said: There are multiple speculations about the evolution of batteries, some with weird claims. There is no doubt that there will be improvements in technology and with respect of size and wight, including the claim of being rechargeable in minutes. But lets look into the basic physics. Lets assume an EV battery of 100kWh. To recharge it in 1 hour requires 100kW of power. To recharge it in 6 minutes would require 1000kW = 1MW. Imagine a service station on a motorway with humble 10 charge columns. That would require 10MW installed power, the power requirement of a small town. But lets look into the charge current. 1MW at 800V results in 1250A charging current. Hard to imagine what cable and connector could handle this. If I'm well informed the actual connector standard allows 25 kW. Not to mention the cell current allowance. Your 25kW refers to type 2 charging connection. There are CCS type of charging going up to 150kW from Audi locally as I have read. Quite a number of 50kW around in CCS. Quote Link to comment Share on other sites More sharing options...
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