No prove lithium 1000 cycles

[SunEagle]

Other than the hobbyists you mentioned earlier I do not see many DIYers using LOC18650. Its irrelevant to compare them to all the other choices. Stick with your Pb batteries.
If you are looking for a Lithium battery to pick on try LIPO. You can add fires to the things contributing to shorter life. California is adding GigaWatts of storage and it is not Pb. Long term it is the economics that will drive who buys what.

No question that Li chemistry batteries can deliver much more power then other chemistry types based on their Ah rating.

But in the end who is paying for that battery? A homeowner performing a DIY / Contractor install or a homeowner paying a POCO through an increase in power costs for all of that Utility GW storage?

All I say is for someone to run the numbers before they commit to a battery back up system.

[scrambler]

As far as I am concerned, a Battery backup system is not about numbers, but about convenience.

If you want relative autonomy during an outage and can afford a battery system spend the dollars...

If you are trying to optimize dollars, stick with simple Solar on grid tied string inverter.

But every one is different with different needs

[SunEagle]

As far as I am concerned, a Battery backup system is not about numbers, but about convenience.

If you want relative autonomy during an outage and can afford a battery system spend the dollars...

If you are trying to optimize dollars, stick with simple Solar on grid tied string inverter.

But every one is different with different needs

I agree which is why I have a 12kw generator that provides a lot of power should the grid go down. But if batteries work for you and you don't mind the cost then go for it.

[Ampster]

As far as I am concerned, a Battery backup system is not about numbers, but about convenience.........

But every one is different with different needs

I agree. With the high rates and shifted time periods in California, it is about the numbers and convenience.

[GeorgeF]

.....
... Stick with your Pb batteries.
If you are looking for a Lithium battery to pick on try LIPO. You can add fires to the things contributing to shorter life. California is adding GigaWatts of storage and it is not Pb. Long term it is the economics that will drive who buys what.

Stick with your PB.
Sure I will stick with my cheap PB till you or others can convince me to switch to LFP. A simple solar user like me do not need a lot of continuous power.

[Ampster]

I am not going to waste my time trying to convince you to switch. From where you are standing Pb is your best choice. Other readers are free to roam about and make a different choice.

[PNjunction]

Yup, stick with what you know. OR, better yet, add to your knowledge with hands-on, and not just discussion.

I enjoy flooded FLA. I also enjoy AGM, especially pure-leads and get some heat for that. But I don't care. It's fun, and I love to hammer them properly with limited solar-insolation challenges. They are easy to undercharge, but *I* know how to maintain them properly. Sunking helped me out and it paid dividends.

But would I power my house with Optima's? No.

What has been preached here before is to start out with a "learner bank" before going big. It's easier and cheaper than before with LifeP04.

Note that I said LifeP04, and NOT anything else like tesla batteries, computer batteries which are *different* types of li-ion. But that's me.

To avoid a ready-fire-aim situation, and if you want to cheaply prove to *yourself* about LFP, even a simple dreaded cheap drop-in these days will let you play not only with cycle life, but all the other factors that you may find fun.

There's a lot of junk out there, but instead of recommending one bang together a 4S / 12v learner bank like I did here years ago, or pop for a $1K BattleBorn, heck even this thing from Amazon has already replaced my pure-lead AGM's just for the fun factor alone:

https://www.amazon.com/TalentCell-Re...9953682&sr=8-8

I can hold this in the palm of my hand. The 48ah Optima Yellowtop that this compares to - can't do that! (Although these LFP's are NOT designed for starter use!)

There are even cheaper examples like the MIADY LifeP04 batteries. Pretty much bottom of the barrel, but still good enough to let one learn even if they want to abuse it - within reason.

So yeah, you don't need to hang LVD, HVD or anything on them. Taken care of in case you biff it.

Speaking of not needing an LVD since it's already built in, here's what's really cool:

With LFP learner bank like this, go ahead and attach a small inverter. Run it until the inverter itself hits it's own dead-man switch at typically 11.7v . That will kick off before the internal lvd in the battery does!

Normally allowing a dead-man switch on an inverter to be your lvd on a regular basis is a big no-no with lead acid. But with LFP, where the voltage range is different, the typical 11.7v dead man switch on an inverter is not a huge worry now! It is actually usable, so one *could* set up a very simple cycling setup with a cheap LFP batt, and cheap inverter, and not worry so much about killing the battery.

This will free you up to investigate the lack of sulfation worries, EQ, ability to use the *entire* capacity if you want, run up to about .5C charge, large discharge. Fully charge it or don't - up to you.

I guess what I'm saying is that something like the above would be like what we would have suggested to a newcomer about going down the nearest store, picking up cheap golf-cart battery to learn on - before trying to design a whole-house system first.

Instead of asking us, your questions will be answered by your own hands-on. While it may not make you switch, it *IS* fun to learn something new. And not that expensive if you consider it a learning instrument that goes beyond mere talk on my end.

Sorry to ramble.

[ThisTime]

I've easily gone past 1000 cycles. In fact, I didn't realize full potential because in real-world use for more than a decade, (not just doing repetetive charge/discharge in a lab), the batteries aged faster than I could use up the cycles!

Reminder - please specify LifeP04, and not just "lithium". Not all lithium is equal. Your cellphone battery is not LFP, and is rated for only 360 cycles.

I usually average about 5 years with a cell phone. That's about when the battery becomes unusable. Roughly 1 cycle per day, probably between 50% and 90% DOD most days, then left on the charger all night. That's over 1800 cycles. I've done this multiple times.

I have a bunch of lithium power tool batteries dating back to early 2014. I don't know how many cycles they have had, but not thousands. The 7 year old batteries are still holding about 75% as much as newer batteries, I think they're dying of old age before I can wear them out.

[Bunker]

I think there may be some misinformation being used as marketing points with LFP batteries. Most marketing information will say something like >6000 cycles or >7000 cycles at 80% DOD. When in reality the spec often overlooked is the recommended discharge rate. LFP batteries subjected to high discharge rates have significantly decreased cycle times. Yes the maximum discharge rate is 1c however the recommended discharge rate is likely .3 or .2c at this discharge rate you will get greatly improved cycle life. It is far more important than the DOD in regards to longevity. Calculate you loads accurately and size the battery bank large enough to keep the discharge rate below .3c. Also define a cycle? Is it each time the battery crosses a certain DOD and rises above a predetermined percentage of charge? Is there a standard that all manufacturers use so the consumer can make informed decisions? Using the >?000 cycles to assess quality is like accepting the advertised 10 year warranty without reading the fine print.

[Ampster]

I think there may be some misinformation being used as marketing points with LFP batteries. .. ....... Is there a standard that all manufacturers use so the consumer can make informed decisions? Using the >?000 cycles to assess quality is like accepting the advertised 10 year warranty without reading the fine print.

No doubt there is some misinformation. There is no standard that I know of.. Since almost all LFP cells are made in China there is bound to be something lost in translation.
To me the decision was based on long term cost of ownership. I have a 42 kWh pack and probably never go above 0.1C and also use conservative charge parameters. I am in a high rate environment in California so using batteries allows me to leverage my solar. Not everyone will reach the same conclusion as I have because their use case and rate environment will be different than mine.

[Bunker]

Sounds like you have a found a great solution to the rolling blackouts! I am putting in 60 kWh because that gives me two days of autonomy before the back up generator kicks on. To me it’s all about being self sufficient. Actually the best case that I could make for traditional lead acid batteries is that they are unaffected by EMP from say a hypersonic missile? I just keep a few extra BMS’s on hand.

[Mike90250]

Sounds like you have a found a great solution to the rolling blackouts! I am putting in 60 kWh because that gives me two days of autonomy before the back up generator kicks on. To me it’s all about being self sufficient. Actually the best case that I could make for traditional lead acid batteries is that they are unaffected by EMP from say a hypersonic missile? I just keep a few extra BMS’s on hand.

If there's hyper-sonic missiles coming in, I'd rather be at ground zero. Where do you get distilled water for the batteries ? what do you eat when the spam and pineapple runs out ? What will recharge the functioning FLA batteries, and what is going to discharge them ???

[Bunker]

I agree however I don’t live in an area that is likely to be a candidate for a first strike. So I will need to do my best with what I have. I have hardened my energy production system and I to the best of my ability planned for such an event. The majority of people effected will not likely have the luxury of going out on the first buss.

[sahucker]

I've easily gone past 1000 cycles. In fact, I didn't realize full potential because in real-world use for more than a decade, (not just doing repetetive charge/discharge in a lab), the batteries aged faster than I could use up the cycles!

Reminder - please specify LifeP04, and not just "lithium". Not all lithium is equal. Your cellphone battery is not LFP, and is rated for only 360 cycles.

Then again, I didn't murder the Lifepo4 batteries by trying to charge them in sub-freezing temps. Nor did I charge them in my hot-garage in the middle of summer. These things are bad. If you're uncomfortable, so are the batts!

The real issue is finding and buying from a reputable dealer/manufacturer. Still after a decade or more of using LFP. Unfortunately, many still get hoodwinked by poor materials.

Its been years since I've wandered around on the solar forums. When we built our system in 2015, I was using inMichigan, but oddly, I can't find the post where I described all the details. Short version of several years of tinkering, at first my 17 cells (I run 1 cells above a normal 16 cell 48 V system, as the 17th cell was planned as a hot spare so to speak) of bottom balanced CALB 100 AH with 14 kW of panel, feeding 4 FM80's and 2 Outback Radian GS8048's with little boards that were not able keep them balanced (it was cheap). I removed them and rebalancing, probably 2016. Now and then, I measured the cell voltage but never found any deviations. It's time to remeasure. The equipment is in an insulated room in the barn that never freezes and provide heavy ventilation in the summer.

Since I'm grid-tied hybrid, I don't usually get much depth of discharge. Just bounce each day from CC pulled down to sell voltage, followed by a minor drop during the evening. A few times a year, an exciting power outage and a chance to run the generator before bed to top off the cells to slip thru the night. A few times, running the batteries to low voltage cutoff because we/wife didn't notice the power was out.

My measly 5 kWh (100 AH) pack was meant to be my learner set in the spirit of school of hard knocks. I didn't know if the LFP prismatic' s ability to withstand high currents would let it survive with 16 kW of inverter. Here we are just, over 2500 day/night cycles on these LFP's.

My plan this fall is to tear it apart. I've 40 more CALB's accumulated, half new, half used. Measure & sort, dump any naughty ones, and rebuild as 17S3P so I can have 15 kWh.

I've logged the kWh in and out of the batteries over a year. I figured the ratio would show a rapid breakdown when the end is near.

5 years.JPG


In March of this year, we had a very long outage, and I did some very heavy charging to get enough energy into the battery so we could make it thru the night. So, this 2022 data point is just Jan/Feb/Apr/May/June/July


ratio.JPG

The 'improvement' in 2022 seems puzzling. I have one idea, Nov21 thru Jun22 I ran several Bitcoin miners to keep the 'room' at 85 to 90F for my wife to use for starting plants.

I will measure all the cells voltages when quiet, both full charged and well discharged for scientific curiosity. .
Long ago I posted the results somewhere, I use one of the MATE3 modes to use the battery thru the night to 'assist' the grid, and 'slowly' drain the kWh out of the battery. I will do that again to see what I've lost. I hope I can find exactly the same settings.

Any other recommended measurements?

[travissand]

I am wondering if now, year 2021, it is already proven that lithium can give lets say more than 1000 cycles @ 80% DoD.

Can someone convince me that I, in 2021, must switch to lithium if my lead acid is near eol ??

Yes it's proven and no I can't convince you. But I might give it a try. My LifeP04 batteries were manufactured in 2010 and installed in government subsidized delivery trucks at an astronomical cost. They were medium sized box trucks with a single axle. 80 kilowatt hours which is a similar capacity as a Tesla car. They spent about 10 years in the trucks making deliveries, no battery coolant system like in a tesla. These trucks weigh as much as 6 Tesla's. Some had electric refrigeration systems some did not. They all had regenerative braking. I got a hold of 10 trucks a few years ago and started repurposing them for off-grid use. I've tested many of them individually and most of them in groups. After all those years of heavy deliveries they're still holding 96% of their rated capacity. On my house my battery is 500 volts and 65 kwh. I've installed these batteries in dozens of locations at client's places on my island. Everybody is happy.

These batteries are beginner friendly and cannot be damaged by misuse because they're fully protected by the computers.

It's not bad to leave them sit nearly dead until the sun comes out next week.

In fact you can let them sit untouched for years. Not even a float charge and they're still fine.

They absorb massive amounts of power even when they're at 99% full so you never miss out on a quick burst of sun like you would with lead acid batteries which hit their absorb voltage so easily. I live in a partly cloudy tropical area and I'm harvesting 30% more kwh per day now that I'm on LifeP04.

The computers tell me exactly my state of charge. No more Hocus pocus and wondering about how much power is actually left in the battery. With lead acids how much they deliver is largely based on how fast you took it. No more fear that you can't make it through the night. You simply know by checking the computer. It'll even tell you how many hours you have left at the current load.

No more changing resistance levels over time which make you have to constantly be relearning and adjusting how you charge and discharge your system.

No more filling flooded batteries or accidentally overfilling a cell upsetting the balance in acid concentration between cells ultimately destroying your flooded batteries. No more degrading heavy stinky bs! No more battery corrosion on the terminals.

Oh and did I mention they won't hurt your back to move them around?

Overall it's completely hassle free. If the inverter shuts down because of low voltage you simply take note that you used too much power today and you better watch yourself closer tomorrow. There's been no damage done. There's no need to start at the generator in fear of your batteries sitting low and being damaged like there would have been with lead acid. You just wait for the sun to come out. And if you can't wait like your refrigerator is starting to get warm go ahead and start at the generator. No you don't have to let the generator run all night it doesn't matter. You just let it run enough to get you through until sunrise tomorrow. Maybe a couple hours and then shut it down. This is what living off grid is supposed to feel like. Pure freedom.

There's a huge amount of people here in the jungle that are completely off grid Since the dawn of time. I personally used a 40 kwh flooded lead acid battery Bank and a 50 kwh AGM battery Bank until their lives were spent. I've seen saltwater batteries nickel metal hydrides nickel cadmium and some other Goofy chemistries. I've talked to their owners. And let me tell you they all suck. This is the first time there's been a chemistry on the market that is so awesome for daily cycling.

New LifeP04 prices have come down so drastically when you compare the reliability, hassle-free traits, increased harvest ability and cycle life with even the most economic lead acid batteries LifeP04 wins so massively that there is simply no comparison. The only time I can recommend lead acid is in standby use where the battery sits on a float charge and is only there for emergencies. Even then I hesitate.