Because of your presentation style, my brain is absorbing the information without undue fracturing! Thanks.

This is one of the most informative videos I've ever watched in regard to SOC on Li-Ion and LiFePO4 cells. Thank you!

Awesome analysis and comparison of the 2 chemistries Andy. Thanks for spending the time to bring a better understanding of the characteristic differences.

Thank you so much for your contributions, the timing could not have been better for me because I’m putting my 280ah system together now so I’m looking forward to your future videos .

Looking forward to dive in to those settings. Your expertise make a lot of sense. Learning so much as always. Cheers my friend

The danger with keeping a near100% full LiFePO4 on a float voltage is that the (poor quality) charger can have an AC ripple with short spikes above 4.2volt even though the DC voltmeter says it is at 3.6volt constant float. Multiply values depending on your battery; 4s, 8s or 16s. Those voltage spikes can cause metalic lithium plating on the electrode, that is permanent damage. I charge my battery untill the first cell reaches 3.65v and then stop for the first cycle of the day. BMS calibrates this event as 100%, after calibration charging is resumed at 92% and stopped at 95%. At midnight the flag for "calibration done" is reset so that it will charge again to 3.65v to recalibrate the next day. The article "Practical Characteristics of Lithium Iron Phosphate Battery Cells" at Nordkyn design discusses the memory effect of not charging the cells to full (3.65v) on a regular basis. It starts building up a hump on the curve which gradually shifts to lower SOC, this means charging to only to 3.4v may reduce the usable capacity over time bacause it reaches 3.4v at a lower SOC. In a truly off grid setup the typical daily cycle would maybe be 70% to 100% (defined as 3.65v) . Where I live there are infrequent events of consecutive rainy days where SOC drops below 10%.

Exactly the information I was looking for - that's kind a scary ;) Unravel all these weird hardware settings would be a real interesting project. Thank you Andy!

I've seen li-ion based cells subdevided into 6 families. LiFePO4 is one of them, there are 3 types with mixes of Nickel, Manganese, Cobalt and Aluminium oxide s. These became popular for cars, power tools and 18650 cells. Most people think of these 3 types when mentioning li-ion. Would be better to refer to them as li-NMC , li-NCA to avoid confusion with LiFePO4.

Thanks. I really need this and the type of info that you plan on posting. I had thought that I would not use a smart shunt just to save money, but now, I see the need for one to monitor the state of charge. It is interesting that counting electrons in the form of coulombs is really the most important measure in relation to SOC. Will be looking forward to your next few videos.

Wow, l learned so darn much from this video. This was one of the most informative videos I have watched about charging LifePO4 batteries. And I watch a lot. THanks so much for your great videos. You have a fan and will continue watching.

Another great video Andy. Really looking forward to a more indepth look at the many unexplained parameters of bms's if that comes up as part if the new series.

Great stuff Andy, I look forward to the following experiments

Merci pour tout ces judicieux conseils ANDY. Bonne continuation.👍

Great unboxing video!😀 Looking forward to the upcoming series on settings.

Andy your research is so helpful No matter how many times I watch your videos I always reference them time to time for help . Helped me get off the crooked grid People wish they could be as cool as us off-grid family ❕✌🏼 Thanks a ton buddy 👍🏼❗️❗️❗️🇺🇸🌞

Great video, and looking forward to your settings series.

Perfect timing Andy, I'm finally setting up my own battery 2.0 and the Smart Shunt is part of that. So I'm keen for a deep dive into the settings.

Great topic, exactly what I need, can't wait to watch next episodes

Hi Andy, more great info as usual. As soon as the temperature in Melbourne rises over zero in Melbourne! I am going out to my van to reset my 200 amp LiFePO4 to use the full capacity (not just 80% to 20% ), THANK YOU! Ok, secondly I am looking forward to the upcoming videos as mentioned, but one thing I would REALLY like you to explore/discuss is "Separate Port" BMS's. There is a lot of poo pooing separate port BMS on the Net, this seems to stem from the lower charging rate available versus the output. Now I agree that this can be a factor in a stationery system with lots of panels, which is why those systems should be a totally different discussion to RV systems. Essentially you really do need a separate port BMS in an RV for obvious reasons, secondly the lower input is never likely to be an issue on an RV simply because you would be hard pushed to get enough solar on the roof to exceed the input valuation. Personally I have a Daly 200 amp output by 50 amp input (dumb) BMS. I seems to be working fine for about two years, but I would really like to upgrade to a BMS that has Bluetooth and is fully configurable, but where to find such as beast? I am aware that "hybrid" BMS's are apparently starting to appear, but I think it is still early has for them. What I really want is something like the JK BMS with the internal balancing (nice), but with a separate charging port, any suggestions? BTW, Daly has very bad communication skills, and don't make it clear you can order a BMS from them to order, that's how I got my 50 amp input model. Also people should note, some distributors of Daly products (like Deligreen) are hopeless, they supplied me with an instruction set for connections for the BMS that was totally wrong and would have blow it up on connection. P.S. They also lie through their teeth. PPS,. currently everything is controlled by my Victron BMV712 networked to the Victron MPPT.

ANDY, everything you just said makes perfect sense. LIfPO's were designed to be fully charged and fully discharged for a certain number of times before degradation sets in. But we all hope in the long run a little less heat when charging will lengthen the serviceable life of the pack. So for me, ill keep it down to 3.55 volts max charge voltage per cell, with a 4 hour float at 3.45 volts. Beer is on me!

Andy, thanks for this fantastic video. Incredibly well done.

I never thought I’d tell a block I’m excited but hey there’s a first time for everything ! I’m excited to see your results and findings Andy Mate. Mate 👍

As usual a very interesting video, Andy. I am looking forward to all the settings. Still strubbling with my absorption and float specs from the Victron RS450(wich I set close together). Hope to see/hear you soon.....

You are an excellent scientist, and I very much appreciate your explanation of charge voltage at the atomic level!

One of your most valuable episode ever. Thank you so much for sharing your thoughts and knowledge. Very much appreciated! 🙏🙏

This is my first experience with you, having only just found the solar garage. I’m extremely interested as I plan to be building an off grid system in the near future & things have changed drastically since I was last fully off the grid. Looking forward to more 👍

Oettinger! 😄👍🏻(I am wondering what it tells about me that this is the first topic I am commenting on on your channel, Andy. 🤣) Seriously, I really enjoy the ride through your experiments and findings. Great stuff. Keep on going!

Exactly the way I understood it after playing with LiFePo4 batteries for a few years. Most knowledgeable videos about these batteries.

Small correction: LiFePO4 is also a lithium-ion battery. They all are. It would be better to distinguish by chemistry: Lithium Iron vs Lithium Nickel/Cobalt batteries. LiFePO4 really doesn't mind being charged to 100%. Keeping them at higher voltage (3.65V per cell) is more problematic since you can actually overcharge. Similarly, keeping them at 0% (2.5V) is generally not good, but anything over 2.5V (say, 3V which is pretty much still 0% state of charge) is fine. In other words, stay away from the very extremes and you're fine.

Very interesting. I am looking for the next videos about this topic

Verry clear explenation Andy, nice job as allways Looking forward to see the results, i kind off winged it when i made my packs. To make full use of the chargers capabilities i even went as far as to make 18S packs and charge them to 64V (max Victron voltage) this would be 3.55V per cell. Dangerously close to 3.65 i guess but in a perfect world... i can never overcharge them. In my installation you can clearly see that at 98%SOC the pack voltage is still only 60V (3.33V per cell) and after that it goes realy quickly, but to prevent cell runaway the batrium lowers the charging rate for the "top balalnce". there are so many cool tools out there to manage your batteries, gonna be nice to see you play with them. Batrium should send you a sample, they are "local" for you i guess... Keep it up Andy, 40K subs soon!

Excellent and really knowledgeable video. Better than most others that really do not know much about lithium batteries.

I saw your eyes sparkle when you looked at those beer plaques! 👍 🍻 It's fun to learn together. We love you to Andy! Be safe all

Thanks Andy - hilarious beginning as usual.😁 Very good topic- BTW I’ve received both my JK BMSs from China, one for my van (12v) and one for home garage (48v) already. I’m impressed with the speed of delivery, obviously air freight! My 400Ah Winston LiFePO4 cells for our caravan are now 6.5 years old, and have been charged usually to 3.45 volts during daily use, and then maintenance charged during storage (we don’t usually use the van in Summer) with a small solar panel (just around 50w, and only late afternoon sun) to a lower state, typically only 3.3v just to avoid any chance of going too low. However I know from experience that : 1. The actual state of charge can be quite low, as the Victron shunt (Bmv 700) gets waaay out of calibration over time, ie: exactly as you said. The ONLY way to recalibrate it is to fully charge the battery. I’ve seen it say the battery is at 100% during storage periods when it’s actually at probably closer to about 35- 40%. 2. My degradation is still absolutely minimal. I have capacity tested them last Summer (Feb 2022) by running an aircon and found the capacity at something significantly over 380Ah- I wasn’t game to go any lower as I didn’t have a BMS on the van, (but will have one soon!) and this means I would have had to watch individual cell voltages personally, just not worth the hassle. Cheers and thanks again.

This will be interesting. Looking forward to all the different opinions here and the facts as you present this.

Neat video Andy, One thing to highlight is that the EV world 20-80% rule is purely about reducing the time it takes to charge not just degradation risk.

12v LiFePo4 im using settings in my SCC LVD at 12.6v and charging voltage at 14.2v i like that setting compared to default (Li) 11.5v LVD and 14.4v charging using a SRNE 40A SCC.. your channel is very informative thank you

Thanks as a lot of good information is always learned from your videos. Keep them coming!

another great video, very informative video with all of the key points I have been needing so far

Looking forward to this series.

Richtig gutes Zeug. Reasons for the coulomb counting being off: - It does not count balancing losses (minor) - It does not count self discharge (minor) - Most importantly: It integrates (adds up) systematic measurement errors (offset, gain, linearity) over long or even extremely long timespans. Even an offset of just 100mA can accumulate to big deviations when no recalibration is done regularly. SoC estimators for NMC, NCA and LTO usually can use the OCV curve to recalibrate to when the cell is known to be outside of the nonlinear ranges at top and bottom. For LFP it is a different story: Your best point for calibration is when the cell starts to become nonlinear at the top end. This is easily recognisable for a BMS observing the rate of voltage change. This is also the reason why e.g. Tesla recommends charging to 100% when you have a MIC LFP model. With respect to ageing: You said it at the end, high voltages themselves will also accelerate degeneration. This is due to high voltages providing activation energy for unwanted side reactions of active material and electrolyte. The c-rate sensitivity also depends on the cell construction. For high power types, high c-rates are not that critical (except for the temperature raise they naturally entail). For high energy types, this congestion and cracking issue is much more relevant. The reaction speed (or for Li chemistries, the intercalation speed) is limited and pushing beyond it increases the energy available to deteriorating processes again (mech., chem.).

Thank you for the info and knowledge sharing! Keep it up!

2nd time watched it . skipped all easy informations those years you gave and i still find new ones.... . thanks.

My car audio batteries get half-ish discharged and recharged several times a day. From 3.2 average to 3.6. The high amperage demand is what I think will kill them before anything else. When I enter in competitions the batteries get abused. My amp-clamp (dmm) has shown over 300 amps on one out of the four 1/0 cables feeding the amps. My home system goes from 2.85-3.48 and NEVER see over 120 amps. Itll outlast the car audio batteries BY FAAR. Excellent video Andy

Can’t wait🧐 getting batteries sometime in June, so will be interested in the info. Love you too! (See I did watch to the end) 😊

Extremely valid information Andy. So we can extend the life span of our, kind of expensive batteries! While utilizing as much of our investment as possible!

Fantastic explanation Andy.

Looking forward to this Andy.

This video was very emotional for me, so many tears Andy. Do you think you'll make a video reviewing your settings in your Charge Controller and Inverter? Would love to see that.

Greetings from South Africa Andy. Cannot wait for this new series, Thank you! Ps. Have you heard about cathodes being Yitterium dipped for preventing heat degredation?

Thank you Andy, just in time my first 16 280Ah cells arrived this week. 🙂

Andy, please explain calendar aging? Thumbs up and still subscribed!

Very interesting! Great explanation.

Outstanding discussion well backed up by theory and practice. I just wish more folks subscribed to that formula for success.

Actually Andy, you are so spot on that I’ve got nothing else to say but…..thanks!

Great video Andy, thanks very much. 🇬🇧

Another great vid, I have often had similar thoughts with all ur testing video experiments, (hours and hours of them), why push the curves? Look forward to ur new coulomb counting methods and trickery. Cheers

The flat charging/discharging curve of the LFP is addictive. Voltage sag was a mayor pain in the arsch with AGM, especially in freezing temps.

As always, Thank You!

Wow and thank you. This has got me wondering now about a control use algorithm to compensate for the drifting of the SOC when controlling use based on Amp-Hour removed. I'm thinking about how alternating the control variable from voltage, to %, to amp-hours removed, and repeat, at a period that could be set or derived, could put into place an automatically compensating SOC

very good, you got a new subscriber here in QLD 👍🏽

Hi from Sweden, I love your videos! 😀

Thanks Andy. Looking forward to the research study and testing. Have you or anyone found any real world research testing on the actual effects of over and under charging with LFP cells? I'll include references to some research papers, which suggest that it's thermal effects that largely contribute to substrate damage, and more a function of charging rate than absorption charge voltage, and that overcharge damage typically occurred at voltages above 3.6v. I could not find one study that suggested did several hundred charge cycles to 3.2v vs 3.6V that I seem to recall found no appreciable degradation until charged to over 4.2V to 4.8V. but if I do I'll add it to this post. Here's some articles that are bit of a dive but give some insights into what is going on at the chemical level: LFP overdischarge conflicting voltage limits - Thread starter Hans Kroeger Start date Jan 21, 2021 DIY Solar Power Forum - Nature Article number: 30248 (2016) 'The Degradation Behavior of LiFePO4/C Batteries during Long-Term Calendar Aging March 2021' - Energies 2021, 14, 1732 "Because the 20% capacity fade and/or 100% internal resistance increase are considered to be the EOL criterion which are widely accepted, almost all of the tests performed in the aforementioned literature are carried out within this battery life span. There are few studies on aging behavior outside this range. Thus, this paper conducted an accelerated calendar aging test on a commercial lithium iron phosphate (LiFePO4) battery over at least 27 months. By considering the storage temperature and SOC level as the stress factors, an aging test matrix was designed such that the tested batteries were subjected to the aging test under five different conditions. Based on the aging results, the impact of storage temperature and SOC level on the long-term performance degradation behavior of fifteen LiFePO4 battery cells was analyzed." 'Failure Investigation of LiFePO4Cells under Overcharge Conditions - 159(5):A678 - researchgate' "The correlation of the changes of cell skin temperature and voltage with cycle number suggest that an internal shorting of the cell was developing with overcharging, which eventually led to the failure. Taking a close look at the temperature curve of each cycle (in the 10th cycle shown in Fig. 2c), the cell-skin temperature slowly increased with time but began a sharp increase at the end of the charge, indicating that the overcharge caused detri- mental damage to the cell components. The same pattern repeated with cycle number for each cycle, and the temperature continued to increase until failure. The temperature increased with charging, then reached the highest temperature at the end of the overcharge process (33◦C at 5.28 V, peak 1), then decreased with discharging; however, after the discharge plateau, the temperature increased again to another peak at the end of the discharge (26◦C at 2.8 V peak 2). As for the tem- perature at peak 1, the temperature increased with the cycle number at a rate of 1.36◦C/cycle, reaching 45.8◦C when the battery failed. It was also noted that in the last five cycles, the temperature increased with a much higher rate, 2.54◦C/cycle than that of the first five cycles (only 0.02◦C/cycle). Compared with the temperature change at peak

Great video. Very informative.

In their product specifications, EVE themselves recommends the SOC window to be 10% - 90% for the LF304 and the LF280K. I always wondered how to do that with such a flat curve. Victron's charge defaults for LiFePo4 are 56.8v (3.55v) for absorption for an hour and 54v (3.375v) for float. Based on your recommendations I dropped the absorption voltage to 56v (3.5v) and left the float at 54v for my two LF304 based batteries. My batteries never drop below 50% SOC so I've never worried about the low end. I charge to 100% (56v) every day.

Your informations are really good, as I just got my new LiFePo4 Bat -Pack! It helps me a lot! I will make 16S4P 280Ah Eve-cells

Great video again good insight into SOC. Have you looked at or tried a Batrium BMS its an Australian company and from my limited research they look great but the price tag is a little high but they do everything you need bar getting another beer from the fridge. Keep up the good work.

Love you and your work here

Hi Andy, new to your channel and building battery banks. I find your content so helpful to me as I'm learning, and how well you explain every little detail. I am in need of new cells, are you able to share the details of where you source your cells from. Thank you for the detailed information you provide on your channel. Regards Des

Hi Andy great video keep up the good work

To add even more uncertainty to the SOC, is charge rate. When charging to 80%, the voltage will vary depending on how many Amps you are charging at.

I made a 100ah 12v lifepo4. I added cheap voltmeter-usb combo to the pack. Digital voltmeter reads 14.9v. I recently bought a smart sensor which reads 13.65v at rest. Been running battery for two seasons no snd.they are amazing.

Ur the best for all of us newbyes in lithium battery world. Fantasik videos

I had to return a lifepo4 pack once because the resting voltage after full charge and then a 10% discharge was 0.04 volts below where it should've been. And what it boiled down to was that it shouldve read 13.3 volts, but read 13.26v, which meant the BMS was cutting off charging up to around 80% instead of 100% from 10 amp "slow" charging But its outstanding that this chemistry can maintain such a perfect voltage curve for the full capacity of the cell. If we can make sodium iron phosphate have that kind of profile, we'll have solved our mass electricity storage problem for good. Fully recyclable, relatively cheap, non-toxic cells encansed in steel and isolated by wax paper.

Danke für das sehr informative Video. Du inspirierst mich meine "Balkonanlage" umzubauen. Victron Laderegler ist schon hier, Hankzor JK ist bestellt. Wenn die Akkupreise wieder gegen Normal gehen werden auch neue (280ah) Akkus bestellt.

Excellent information Andy, much appreciated. Can’t wait for video series! Are you still experimenting with the GTIL2 grid tie inverter?

I appreciate the graphs showing the difference between Lion and LiPO4. Unfortunately, my Bluetti solar generator was not charging its LiPO4 batteries properly. They overheated at 100%, because they bulk charged to almost 99%. Its 30C here, but no excuse to not being able to function properly when I have a BIG fan blowing on it! I told customer service, but no one understood my technical question to update the firmware. I now know where their charge rate was improper. Returned my EB3A, since it could never achieve proper life expectancy!

Hey Andy - A test idea for you: Variable discharge rate curves. Many times we have seen you show us the flat voltage curve of LiFePO4 when discharging (or charging) between 90% and 10% state of charge and with the knees at each end of the SOC. Most of these show the curve when tested with a constant discharge rate. I was wondering however what the discharge voltage curve looked like if you programmed a variable rate of discharge, say cycling between 0.1C and 1C for 5-minutes at a time, or some other variable load profile. How much "wobble" would the voltage display when a battery is being discharge with variable rates? You have a battery tester which can be programmed to run such a test I believe. It seems to me that variable rate of discharge would be a more realistic test of the demands placed on many batteries. Thanks and keep up the good work.

Awesome explanation

Nice work !

Well my new off-grid hunt camp power system goes active tomorrow. 520 watts of solar panels powering a 40 amp SCC to a 12v 200ah DIY Lifepo4 battery. I've been watching all of your videos along with Will's DIY solar forum and I'm still confused on what parameter settings I should use. You say charge to 3.4 (13.6) but what voltage should I use to start top balancing my battery? Guess I should rewatch some videos to see what I probably missed the first time. Really enjoy your videos and the time you spend finding and suggesting new or better possibilities for this battery chemistry. 🇺🇸☀️🍺

Thank for the eye opening information in this video. I was very interested in being shown the mechanism that causes degradation on charging. Does it work the same way on high discharge? I often see comments advising a max discharge of .2C for maximum battery life. Is that strictly true?

Hi Andy. Great Idea! Please include in to the scope also solar charge controller setings. E.g. where to set a voltage of 3,4? Is this in SCC or BMS etc. Another topic is why not to read state of charge from BMS using CANBUS vs using SmartShunt? Maybe this is clear when you are at battery version 2 or 3, but for those who are at version 1.2 there are a more questions than answers

Thanks Andy

Another thing to consider might be the swelling that occurs while charging and discharging. I don't know how much this physical movement of the cells contributes to degradation, but the swelling on my cells tends to occur more at above 3.35V/cell (26.8/8 cells). I also consider how long my battery will play my stereo at full volume and whether or not it's long enough to make me happy. Will my hearing be degraded before I need to replace my battery? Time will tell the result of that experiment. You might want to consider/research adding closed captioning to your videos in the long term😁 Thanks for your input. I have enjoyed your videos 👍

Finally gonna be some videos on how to set up the bms parameters. I've contacted overkill about doing some videos on custom bms settings. They said it was a good idea but haven't seen anything yet. I have 6 280AH strings of batteries with 6 over kill 48volt bms and haven't used my batteries at all because I'm trying to figure out how to navigate the xiaxiang app. I want to do the max amount safely and with longevity. Also what is the charge rate? What about the float? Obsorb? Like to see how to do the bms settings. I have trouble naming all 6. I got 1 named but the app refused to let me name the other 5.

the bench is clean and free - looks like new project on the horizon but that was just at the beginning of the video before you unpacked that lot of stuff.

Correct me if I’m wrong Andy but most BMS do not start passive balancing until 3.5 V so charging to 3.4 V Will mean the BMS won’t balance the cells. The way that I look at batteries is they are a consumable item that is going to wear out over time i.e. lose capacity slowly no matter what you do you may prolong the life by only months maybe a year , it really comes down to how hard you cycle the batteries from my experience if the batteries are cycled hard you get an average of about three years out of the batteries where you have now only 80% of your original capacity regardless of how you try to look after the batteries, Like you said it depends on the C rating of your discharge so the more capacity you have the longer your batteries are going to last. The most problems I’ve seen with lithium batteries in the caravan and camping style of things is generally cell in balance over time reducing the overall capacity. I really like the effort you’re going to and I realise how much time you put into these videos thank you for busting some of the myths out there.

Seems to me if cells are not perfectly ballanced, Smart Shunt is not enough. It won't protect single cells to go in "unhealth" voltage teritory. Each cell should be measured and BMS should send commands to charger to lower the charging current. All three of them. Maybe use some kind of BMS system with master and slave shunts capability. Or just rely on three batteryes. If one BMS disconects its battery, the other two are still running, and the system stays on. But if you have just one battery, BMS must comunicate with charger. Only the charger should finish charging, not the BMS (by disconnecting the battery). Can't wait, what is further going to develop in this project. Top work Andy. Respect!

Andy - you're correct theoretically, but in a practical sense you can get pretty close to a % by selecting a voltage AND a time. I want to have about 65% in my battery each morning, so I set it to charge between 2-5am to a voltage of 53.7v. Every single day this gets me 65-67% full as per the JK BMS readout. It quickly hits the voltage & holds, then the capacity slowly creeps up. So you need to "learn" what voltage level & how long & then you can practically get a specific % pretty reliably. If it starts at 0% maybe i'll get 61%, if it starts at 40% i'll see my 65% within that timeframe of charging. Hope that helps!

I agree with Paul, perfect timing. Just finishing the SFK V3 kits, charging them and in the meantime hanging the new inverter and getting ready to commission Solar V2.0 It's all very exiting Andy and I'm looking forward to the next videos. BTW, should I be allowing some room in the system for a bilge Pump or is that a Queensland thing?

Appreciate the explanation and frankly was quite surprised. My Lifepo4 battery manufacturer wants me to charge it with 14,6V only. I guess they want to sell me new batteries soon? :)

Ich liebe es, wenn du tust, was du eben tust..🤣🤣 Andi hör bitte niemals damit auf.. Der Anfang des Videos ist so bisl wie Weihnachten, beim zuschauen was die anderen so auspacken..🤔 Und dann bringst wieder ein grübeln in die meisten Gesichter.. Mach bitte weiter und weiter und weiter.. Wozu zum Geier brauchst du ne Bilgepumpe ??? 🤓

in my experience 54.4 to 50.4 is the best compromise also because the remainder is very low. the difference also lies in whether you have 1 battery pack or multiple packs in parallel. I have 4 packs in parallel and once a month I bring everything to 55.2 to make sure that the cells are really equally charged and I reset the shunt

Andy, I have always agreed with you regarding not charging to 100% max. Something to also consider is how the battery is being used. I have 2P4S 560AH(LF280 cells) battery on my sailboat. The battery can be charged 3 ways: [1] shore powered charger(5A to 65A), [1] solar(350W), and via alternator(120A). Since I have been mainly day or over-night sail, I rarely charge via solar(keep flexible panels safely stored) or alternator because of the large capacity compared to my needs. When I am not sailing, the vessel is connected to shore power. I have the charger set for 45A boost charge to 14V(3.5V average cell). It stops charging until the battery hits a "boost return voltage" of 13V. This take about 3 days with loads mainly being for my refrigerator, computer, and networking. I could set the return voltage lower but I want to be able to randomly show up and go sailing with still plenty of capacity. I have a JDB SP04S034 200A BMS which has both bluetooth and RS485 communications. I readout the RS485 with a raspberry pi via a simple python program which creates plots for 2hours, 48hrs, and 7days windows. I can connect to the sailboat's raspi remotely via vnc to view the monitoring plots. It is interesting to note the cell deltas increase and then decrease during discharge cycle at what I call a "mini-nee", which is the at the 3.3V to 3.2V cell voltage drop. I wish I could send you some plots. The delta raises up only about 20 mV but then drops back down is a rather symmetric fashion. My guess is some change in a phase transitions.

Very valuable information Andy. I am glued to your presentations. I have a question. If you have 3 150A batteries (in parallel) charging at 0.2C, would you set the Charge Controller at 30A or 90A ?

I keep it simple and set my BMS to 3.0 and 3.5 for now. I will adjust as your videos indicate otherwise. Should I need more current overall I will add more cells as I go. It spreads out the cost and the prices seem to drop a bit each year. EZ-PZ. Thanks for the video.

Good morning Andy .thank u for your expert info, you've got more know how then me so u are an expert to me.I do like what u have to say on this subject.ok now I have something u might like to read from my experience with your purchase of the bilge pump I didn't see if its 12 or 24 volt but I buy THEM by the dozen😁,ha! ha! Ok, but when I do get them I usually purchase 2 or 3 they don't like long pumping cycles,I put mine in our fish pond to activate the water fall,in my pond it runs for between 1-3 hours and not every day usually in the summer months,what will u use yours for I'm keen to know that Andy,cheers Rene from sunny cloudy Vic.🥰

excellent as always ... smiles .. beerwah swamp is appearing again above the water line .. the grass has grown deep and the sun is once again shining upon us ... lol..

Heya. you made it very clear the why and remember lifipo4 don't have a "memory"