sdh Posted August 14 Share Posted August 14 Hi, I am interested in any strategies folks are following with their evening drawdown of their household lithium ion batteries now that we are not currently loadshedding? I previously did not go under 40% for most timeslots and 60% in the early evening to avoid blackouts. Am considering going a bit more aggressive! Cheers Stephen Quote Link to comment Share on other sites More sharing options...
sdh Posted August 14 Author Share Posted August 14 With the objective to maximize electricity and carbon savings without killing my battery (if that is even still a thing). Quote Link to comment Share on other sites More sharing options...
sdh Posted August 14 Author Share Posted August 14 5kw lithium iron phosphate battery Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted August 14 Share Posted August 14 1 hour ago, sdh said: Hi, I am interested in any strategies folks are following with their evening drawdown of their household lithium ion batteries now that we are not currently loadshedding? I previously did not go under 40% for most timeslots and 60% in the early evening to avoid blackouts. Am considering going a bit more aggressive! Cheers Stephen You can adjust down to 25-30% now that there is hardly any LS. If power failures take place in your area then adjust to suit your household. This should not reduce the battery to below 10yrs I guess. sdh and WannabeSolarSparky 2 Quote Link to comment Share on other sites More sharing options...
sdh Posted August 14 Author Share Posted August 14 46 minutes ago, Scorp007 said: You can adjust down to 25-30% now that there is hardly any LS. If power failures take place in your area then adjust to suit your household. This should not reduce the battery to below 10yrs I guess. Thanks! Quote Link to comment Share on other sites More sharing options...
Bobster. Posted August 14 Share Posted August 14 (edited) I used to have my system set so that SOC would not go lower than 40% whilst grid was available. Additionally I had a rule on my system to charge the battery from grid if necessary starting at 15:00, so that it would be full by 16:00, which puts me in my cozy little comfort zone. If the battery is full at 16:00, I'm good until at least 9:00 the next morning. I can't say I was cautious, it's fairer to say that I was absent minded. I didn't change any of this. About three weeks ago we had a burned out cable and then an overloaded sub station in my neck of the woods in the small hours of the morning. The day before had been overcast, and if I'd just left the system to it's own devices I would have had maybe 50% in the battery at 16:00. As it was the battery had plenty in it the next morning, and we were able to keep all the backed up circuits going until power was restored. We just had to resist the urge to run the dishwasher and the geyser (which we may actually have got away with, but in real time I took the pessimistic view). You can never be 100% protected, but when you have PV with batteries you can buy yourself some time when the stuff hits the fan. If you have 10 kwH, as I do, you can buy quite a few hours if the sun doesn't shine that strongly. I paid for maybe 4 units of electricity the day before - call that R10. But I was able to work the whole of the next day, and I get paid by the hour. Bargain! Edited August 14 by Bobster. Make the post longer. I'm like that. sdh 1 Quote Link to comment Share on other sites More sharing options...
Bobster. Posted August 14 Share Posted August 14 2 hours ago, sdh said: Hi, I am interested in any strategies folks are following with their evening drawdown of their household lithium ion batteries now that we are not currently loadshedding? I previously did not go under 40% for most timeslots and 60% in the early evening to avoid blackouts. Am considering going a bit more aggressive! Cheers Stephen Me again. My strategy really remains unchanged. Do as much as I can whilst the sun is shining and then just coast through the night. Sure it's been 120 and eleventy seventeen days since we had load shedding, but you can still save a bit on your electricity bill. zsde 1 Quote Link to comment Share on other sites More sharing options...
sdh Posted August 14 Author Share Posted August 14 20 minutes ago, Bobster. said: Me again. My strategy really remains unchanged. Do as much as I can whilst the sun is shining and then just coast through the night. Sure it's been 120 and eleventy seventeen days since we had load shedding, but you can still save a bit on your electricity bill. Thanks! Quote Link to comment Share on other sites More sharing options...
system32 Posted August 15 Share Posted August 15 I use 30% SoC on 4 x Hubble AM2 (~20kWh). Lasts most nights. Only recharge from Solar. Quote Link to comment Share on other sites More sharing options...
GMAC Posted August 15 Share Posted August 15 I have my 10kw battery soc set at 50% lucky never gets there. Lowest it gets to is 55% but most mornings around 65% as the solar starts to take over in the mornings Quote Link to comment Share on other sites More sharing options...
sdh Posted August 15 Author Share Posted August 15 2 hours ago, system32 said: I use 30% SoC on 4 x Hubble AM2 (~20kWh). Lasts most nights. Only recharge from Solar. thanks Quote Link to comment Share on other sites More sharing options...
sdh Posted August 15 Author Share Posted August 15 3 minutes ago, GMAC said: I have my 10kw battery soc set at 50% lucky never gets there. Lowest it gets to is 55% but most mornings around 65% as the solar starts to take over in the mornings thanks Quote Link to comment Share on other sites More sharing options...
Beat Posted August 31 Share Posted August 31 (edited) The specification of my LEOCH 48100TB batteries reads like this: Guarantee: 3500 cycles at 100% DOD. That to me means 2 things: 1. Batteries are designed to be used up to 100% DOD. 2. If I use them systematically with less DOD I expect much longer lifespan. 3500 cycles means almost 10 years at 1 100% DOD per day. Who does this every day? In addition I think that extreme charge and discharge currents deteriorate the batteries more than DOD. I try to keep them at 0.2C with extremes to 0.4C. Edited August 31 by Beat HendrikBigChief 1 Quote Link to comment Share on other sites More sharing options...
TaliaB Posted August 31 Share Posted August 31 3 hours ago, Beat said: Batteries are designed to be used up to 100% DOD I can agree with above statement to discharge to 0% Soc on occasion would not damage your Lfp battery but never leave it at 0%Soc for long periods. By far the worst culprit for damage to Lfp is high temperature that is caused by high charge/discharge cycles. The recommended charge/ discharge is 0.2C and on occasion for short periods 0.5C( surge currents) but never 1C if you find yourself consistently in that territory, rather opt for a second battery in parallel. Consistently charging to 3.65v/cell also puts unnecessary stress on the cells so opt for absorption voltage that triggers the bms balance cycle that is normally on the start of the upper flat curve around 3.35v/ cell. Thus the importance of battery/ inverter communication the bms will take care of the cells. WannabeSolarSparky 1 Quote Link to comment Share on other sites More sharing options...
Paulcupine Posted September 3 Share Posted September 3 Cycling from 100% -> 10% -> 100% is totally fine. The Freedom Won warranty is reduced from 10 years to 5 years if you *regularly* discharge below 10%, as an example. On the other hand there is little point in cycling your battery lower then you have the ability to charge it with solar the next day. Also, degradation of the battery happens just as much at high cell voltages as low ones. Go and watch some of Off Grid Garage's battery testing videos on youtube. This guy makes excellent content. Quote Link to comment Share on other sites More sharing options...
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