I really think that you could learn a lot from reading the actuall datasheet from the manufactures. The tell you exactly how to charge and discharge. You are trying to extend the life from 10 to 30 years? You need to understand the expected life, not the max you can stretch it if you micro cycle it. Everyone know that keeping it between 20-80% will maximise life, but how much do you really need to make them last before calendar aging get them? It is all relative.
always follow Factory Spec. design engineers have put a lot of time, money and labor into high end batteries and they know their product better than anyone, over the decades I have run tests to both extremes to find the fudge factor built into everything LOL as a design engineer there are only three youtubers I trust on the topic Will, Dave Poz & jehugarcia everyone else is a trailer rat with a harbor fright meter BAHAHA rule #1 dont get all your information from youtubers hahaha and if you do, you never get what you want, you will however get what you deserve :)
I think Will is mainly talking about store purchased 12v-48v batteries with pre installed BMSs. DIY setup's like yours, you are also correct. Most people won't be paying attention to their cells like you and I. For them it makes sense to charge to 100% to minimize problems.
He explained all your points, in video previous to one youre talking about. Battery for peak shaving is paid in 5-6 years, LFP battery even if charged / discharged to max will last 10 years, so it does not matter what i do with that battery (if i stay in BMS limits) because investment is paid. That was his point. BTW Texas Instruments chips are only good chips for batteries.
i think another thing to consider is that most batteries nowwadays are underrated. ie they have more than advertised capacity. So using the full 100% of the battery might not actually be 100% of the stored energy. Also the degradation over time you will have close to the remaining capacity over time. this is predictable behaviour and well within the expected lifespan. Would your way make them last even longer? Perhaps. but Calendar aging will probably kill them before charge/discharge behaviour. Also, your "knee points" most of the capacity is within that range, probably 95% or more at least. I also dont think anyone is really suggesting charging cells to 3.65+volt and discharging them to 2.5v Did anyon ever claim this is how they should be used? If so, please quote that recomendation as I would love to dispute it.
0, 2.5v to 100 3.65v is what Will is saying is ok. How do you come up with a different interpretation? The point is, heavily repeating going past the knee points throws the cells out of balance the more you do it requiring periodic top balancing. That's the biggest issue, how much more longevity you get whether it gets or loses you another 1000 or more cycles is money gained or thrown away so that's relevant to how important that is to someone. There aren't many things that can take extreme use without consequences. Life lessons teach you that, so I keep my gear use under what is claimed it's capable of. Victrons gear reputation is they're battle tanks so I used them at extreme duty & got about a years use each out of 4 of their 150/100 chargers. You can go by Will's advice if that floats your boat but I stand by my experience & what I've learned from reading as that's pretty wreckless use of lithiums.
@@bossroxdiysolar actually we agree on everything that you just stated. Going from 2.5 to 3.65 is manufactures SPEC, in the data Sheet. but that is not meant for everyday cycling, but instead for testing only. I charge to 3.45v/cell myself, and dont really have a lower limit as I never get close to it living off grid. but if I did need to go lower on occasion, I would have my cut off at 2.5v/cell. first cell to hit 2.5v cuts the whole 16s pack. But your system should be sized properly so that you are not having to squeeze every aH out of it. My system consists of 20kWh of storage, and over the evening doing cooking and AC/Heat pump, water pumps, tv, internet, etc I go down about 30%. not TO 30%, but I have 70% remaining in my batteries every morning when the sun starts charging. Recharge down by noon everyday, while running all those things like electric HW, AC, all the toys come off before the remaining is going to batteries. My point is that you you can be right and wrong at the same time. Another example. I own a Tesla, and when I am driving I have the battery set to 70% top charge limit and recharge it every night. I rarely let it go below 30%. I do this because I want it to last. that being said when I road trip, I charge to 100% before I hit the road, and I have taken it to 4% to reach my destination. Do i do that e ery day no, but I can occasionally. So before calling out the largest solar advocate on youtube by name for clicks, think about all the aspects. I am not your average DIYer as I consult professionally on SOLAR projects for resi and Comm systems. and I live off grid entirely with no grid access. The system I have sized is sized so well in fact that I do not even have a beckup generator, haven't needed one yet. Even if I did have one, I have not yet wired the generator input to an outlet hahahah. No need to be nasty, just learn and think about all the perspectives. One last thing, your can ONLY top balance cells above 3.5v, so occasionally they need to be charged above that for a true balance.
@@sNEAKYnIGHTmUPPET I'm off grid as well. 33kw in panels, 60kw storage, 600 amps charging & 22kw in inverters all @ 120v. 3.45v is a good #, I do 3.42or3. This ain't for clicks, I don't ask ppl to subscribe & I certainly can't make any green on my channel or care to, just ain't got the right stuff or ambition to take it any further. Nor does it matter, I do quite well with my work. Just passing along info as I go along to help others with what I learn & not make some of the bad choices I have in this journey. I haven't run across anyone on here with a unique set up like I got nor do I think Will has the depth to go as far as I have with solar so I got a pretty good grip on how things work.
I found a deal I had to drive 400 miles, I got 14 Telco batteries from a cell tower that was being moved, they had been stored and when I got them they were all at 12.61v ran through a few cycles and they are all at new factory spec. between my Inverter and charge controllers I should never be out of range?
Why can't someone invent a BMS that charges cells individually , without shutting down a whole pack. To me, it makes no sense for my whole pack with enough voltage, to shut down , because one crappy cell needs to shut down. Is there no way to have a separate charger for each cell?
Most of what I've learned about solar power is from Will but I get information from other people before I make a decision on what to do.
I really think that you could learn a lot from reading the actuall datasheet from the manufactures. The tell you exactly how to charge and discharge. You are trying to extend the life from 10 to 30 years? You need to understand the expected life, not the max you can stretch it if you micro cycle it. Everyone know that keeping it between 20-80% will maximise life, but how much do you really need to make them last before calendar aging get them?
It is all relative.
always follow Factory Spec. design engineers have put a lot of time, money and labor into high end batteries and they know their product better than anyone, over the decades I have run tests to both extremes to find the fudge factor built into everything LOL
as a design engineer there are only three youtubers I trust on the topic Will, Dave Poz & jehugarcia everyone else is a trailer rat with a harbor fright meter BAHAHA
rule #1 dont get all your information from youtubers hahaha
and if you do, you never get what you want, you will however get what you deserve :)
I think Will is mainly talking about store purchased 12v-48v batteries with pre installed BMSs. DIY setup's like yours, you are also correct. Most people won't be paying attention to their cells like you and I. For them it makes sense to charge to 100% to minimize problems.
He explained all your points, in video previous to one youre talking about.
Battery for peak shaving is paid in 5-6 years, LFP battery even if charged / discharged to max will last 10 years, so it does not matter what i do with that battery (if i stay in BMS limits) because investment is paid. That was his point. BTW Texas Instruments chips are only good chips for batteries.
i think another thing to consider is that most batteries nowwadays are underrated. ie they have more than advertised capacity. So using the full 100% of the battery might not actually be 100% of the stored energy. Also the degradation over time you will have close to the remaining capacity over time. this is predictable behaviour and well within the expected lifespan.
Would your way make them last even longer? Perhaps. but Calendar aging will probably kill them before charge/discharge behaviour.
Also, your "knee points" most of the capacity is within that range, probably 95% or more at least. I also dont think anyone is really suggesting charging cells to 3.65+volt and discharging them to 2.5v
Did anyon ever claim this is how they should be used? If so, please quote that recomendation as I would love to dispute it.
0, 2.5v to 100 3.65v is what Will is saying is ok. How do you come up with a different interpretation? The point is, heavily repeating going past the knee points throws the cells out of balance the more you do it requiring periodic top balancing. That's the biggest issue, how much more longevity you get whether it gets or loses you another 1000 or more cycles is money gained or thrown away so that's relevant to how important that is to someone. There aren't many things that can take extreme use without consequences. Life lessons teach you that, so I keep my gear use under what is claimed it's capable of. Victrons gear reputation is they're battle tanks so I used them at extreme duty & got about a years use each out of 4 of their 150/100 chargers. You can go by Will's advice if that floats your boat but I stand by my experience & what I've learned from reading as that's pretty wreckless use of lithiums.
@@bossroxdiysolar actually we agree on everything that you just stated. Going from 2.5 to 3.65 is manufactures SPEC, in the data Sheet. but that is not meant for everyday cycling, but instead for testing only. I charge to 3.45v/cell myself, and dont really have a lower limit as I never get close to it living off grid. but if I did need to go lower on occasion, I would have my cut off at 2.5v/cell. first cell to hit 2.5v cuts the whole 16s pack.
But your system should be sized properly so that you are not having to squeeze every aH out of it. My system consists of 20kWh of storage, and over the evening doing cooking and AC/Heat pump, water pumps, tv, internet, etc I go down about 30%. not TO 30%, but I have 70% remaining in my batteries every morning when the sun starts charging. Recharge down by noon everyday, while running all those things like electric HW, AC, all the toys come off before the remaining is going to batteries.
My point is that you you can be right and wrong at the same time. Another example. I own a Tesla, and when I am driving I have the battery set to 70% top charge limit and recharge it every night. I rarely let it go below 30%. I do this because I want it to last. that being said when I road trip, I charge to 100% before I hit the road, and I have taken it to 4% to reach my destination. Do i do that e ery day no, but I can occasionally.
So before calling out the largest solar advocate on youtube by name for clicks, think about all the aspects. I am not your average DIYer as I consult professionally on SOLAR projects for resi and Comm systems. and I live off grid entirely with no grid access. The system I have sized is sized so well in fact that I do not even have a beckup generator, haven't needed one yet. Even if I did have one, I have not yet wired the generator input to an outlet hahahah.
No need to be nasty, just learn and think about all the perspectives.
One last thing, your can ONLY top balance cells above 3.5v, so occasionally they need to be charged above that for a true balance.
@@sNEAKYnIGHTmUPPET I'm off grid as well. 33kw in panels, 60kw storage, 600 amps charging & 22kw in inverters all @ 120v. 3.45v is a good #, I do 3.42or3. This ain't for clicks, I don't ask ppl to subscribe & I certainly can't make any green on my channel or care to, just ain't got the right stuff or ambition to take it any further. Nor does it matter, I do quite well with my work. Just passing along info as I go along to help others with what I learn & not make some of the bad choices I have in this journey. I haven't run across anyone on here with a unique set up like I got nor do I think Will has the depth to go as far as I have with solar so I got a pretty good grip on how things work.
I found a deal I had to drive 400 miles, I got 14 Telco batteries from a cell tower that was being moved, they had been stored and when I got them they were all at 12.61v ran through a few cycles and they are all at new factory spec. between my Inverter and charge controllers I should never be out of range?
Lithiums?
Why can't someone invent a BMS that charges cells individually , without shutting down a whole pack. To me, it makes no sense for my whole pack with enough voltage, to shut down , because one crappy cell needs to shut down. Is there no way to have a separate charger for each cell?
That's a great idea, I don't see why that can't be done but like I said staying within the knee still gives you just about all the cells capacity.
i think that's called an active balancer.