لقد كنت أرغب في إنتاج هذا الفيديو لفترة طويلة جدًا ولكني كنت أعلم أنه سيكون من الصعب تصويره. لقد قيل لنا جميعًا أن نقوم بشحن بطاريات LiFePO4 بشكل أساسي مثل الرصاص. قد تضيف شركات أجهزة التحكم بالشحن ميزة Li، لذا تعتقد أنك بحاجة إلى شراء أحدث معداتها ولكن انظر تحت الأغطية وستجد أن دورة شحن Li الخاصة بها هي مجرد دورة رائدة مع ضبط وقت الامتصاص على 0. إنها مجرد خطوط أسرع . من المؤكد أن الشحن بهذه الطريقة سيوفر الطاقة للبطاريات ولكن على حساب تقصير عمرها الافتراضي. في هذا الفيديو، أبذل قصارى جهدي لوصف الطريقة التي يريد بها Li حقًا أن يتم توجيه الاتهام إليه. يعتمد هذا على بحثي الذي قرأت فيه جميع الأوراق والنتائج التي يمكنني العثور عليها من العلماء الفعليين الذين يعملون مع هذه البطاريات وخاصة الأشخاص الذين يختبرون هذه البطاريات لدورة الحياة. إنهم لا يشحنون بطارياتهم مثل الرصاص. الشحن إلى الجهد الكهربائي يضر بفترة Li. إذا كنت تريد البدء في مشروعك البحثي الخاص بهذا الأمر، أقترح عليك قراءة مقالة كونراد المرتبطة بأسفل صفحة الويب الخاصة بـ BankManager أدناه. إذا كنت ترغب في معرفة المزيد عن BankManager الخاص بي، فيمكنك العثور على هذه المعلومات على الرابط إلى الفيديو الهندسي الموضح. هل لديك أسئلة أو تعليقات؟ اتركهم أدناه! نحن نبذل قصارى جهدنا لقراءة جميع التعليقات والرد عليها على قناتنا. ———– روابط للمنتجات التي نحبها (روابط تابعة لأشياء نمتلكها ونستخدمها ونوصي بها بالفعل. لا تدفع لنا الشركات أبدًا أي أموال مقابل تأييد المنتجات. إذا كنا كذلك، فسنخبرك بذلك) الفيديو): يرجى الاشتراك والنقر على الجرس لمشاهدة مقاطع فيديو جديدة كل أسبوع والمزيد من المحتوى مثل هذا. قم بتوصيل ودعم قناتنا Patreon: PayPal: اشتر قمصان S/V Temptress وغنيمة: تحقق من منتجاتنا المفضلة على Amazon: #emilyandclark #emilyandclarksadventure #svtemptress |موقع قفشات
49 تعليق
This may be the single best overview of LiFePO4 battery charging available. I have also purchased the BankManager and tested it on my bench and it works as advertised. I've done my best to confuse it or break it and failed on both counts. Highly recommended.
You should of had two demonstration rigs, which you show adding the 'bank-manager' device & its Bluetooth or control system. Holding the kit up doesn't do if justice imho
"You can abuse a Lead Acid battery"
Errr… NO.
If By "Abuse" you mean discharge below 50%, you certainly CAN'T
Sorry Clark – I can't stand hearing that bell. Could you maybe change it to a wave on the beach or something? I really can't watch your videos any more. sorry sorry. and the music is fine because I can skip it, but it's very annoying to hear it every time, too. Good luck and it's a shame because I would otherwise watch them all!
Good choice on the title of your channel!
Nice video, with the information very well presented (as usual). If I may add on a bit, the "Charge to 80%" thing for electric vehicles is specifically because of the use of NMC (and related) Lithium battery chemistries that really don't like to sit at full charge. They also don't like sitting at low SoC either. "Keep them between 20% and 80%" is the rule for maximum life in most EVs. My own EV is from 2010, and the original LCO-based battery still has 80% of its capacity after nearly 15 years / 62,000 miles on the road; that rule is ingrained in the car's battery management strategy, and it appears to have worked.
The LiFePO4 chemistry doesn't suffer from this, so if you buy a car with LiFePO4-based battery cells you can charge them all the way up and drain them down pretty far on a daily basis without worrying about damage. That can substantially make up for the lower energy density of the LiFePO4 cells in the EV environment.
So what that means for LiFePO4 batteries in RVs and boats is that we don't need to worry quite so much about battery stress due to high SoC. It's still very important not to overcharge them, as you point out, but bringing them up to a proper 100% and leaving them there should be fine.
Granted more expensive, but I wonder if it would help to have two systems, albeit connected, to switch back and forth to. That way you could isolate one system to use while the other one gets properly charged
If I wanted to learn about 'lead', I would have watched THAT video..
I bought li-time lithium batteries along with their charger. I have always used the charger to top off/full charge the batteries. Is it hurting the batteries 400 ah in series for my van conversion? Do I need to turn off the solar occasionally?
Hi Clark, will the Bank Manger plus take the place of a BMS in a home built battery? Thanks
Weird my charges are charging lithium to 14.7 thsn disconnects and it trickles ?
Midnite solar, the kid , charge controller, ,is designed so you can charge all the batteries. It is infinitely controllable and every metric is user adjustable
The sun dictates the charge rate lol, for most of us buying into it nowadays
Great presentation Clark. I just got an email from Redodo announcing that they have created a 140ah dual purpose battery with ~900 CCA that can start engines. Sounds like a great idea for your next video. Thanks for the great videos.
This video, amongst other positive things, shows why LiFePo4 is a nightmare of complexity to you averagage user. This is why 'non specialist' people have to buy black boxes, fit and forget, and not really have a clue about what's going on! One other thing for sure: hybrid (LA mix) is a must for any boater.
This guy is wasting your time….making things more complex then they are. He do not physically understand what is happening, reason he can't put the simple logic of a LiFePo4 into words.into words
One situation in which it is beneficial to always charge your LFP battery bank with wall current is for security guards first responders who simply are trying to have lots of current available for either 12 volt devices or other devices that they would run using an inverter and they are trying to save on gas. They don't want to use a DC to DC charger to recharge their battery bank. They want to go home at the end of every night, plug it in, and get cheap electricity.
Of course you charge to a voltage for LifePo4. Absolute Max is 3.65 volts per cell. For maximum life the 3.45 volts per cell(if the battery’s balance function works that low) the difference in capacity between these two voltages is negligible. The lowest you can take a cell is 2.5 volt per cell but most people stop at 3 volts. A good BMS (battery management system) won’t allow the battery outside of these ranges. There are only two points where capacity on a lithium battery is true, full and empty voltage with little to no load. Anything in between is a rough guess and only a coulomb meter is accurate and that is initially set at the full voltage. A good charge control will not abuse the battery and keep the BMS from stepping in(the last line of defense). The charge control will have settings like bulk or absorb (3.45 volts per cell) tail current, the amount of power as it reaches full or bulk and absorb time. The better your cells are balanced and the better quality of the BMS’s balancer(active type) the less time is required at the higher voltage. The less time at the higher voltage the better. There may be a setting called float. Lithiums don’t really need float, so I disable it or set it to 3.35 or less. All voltages I gave are per cell. A 12 volt has 4 cells, 24V has 8, a 48V has 16. Heat is indeed a killer of lithium so under hood temperatures should be reserved for lead acid batteries. Always use the recommended voltage printed on the battery if you can’t change the settings like balance start voltage via Bluetooth (3.4 Volts per cell). Lastly if you need a 48 volt battery, buy a 48 volt battery. Do not put 12 volt batteries in series because they will become unbalanced. There are too many variables to be answered here so ask questions on forums like DIYSolar
Thanks Clark, lead carbon is looking better every day….
Thank you. Excellent. I am still going to watch it a second time because my system is strange: No solar (for charging batteries). Daytime production is high enough to run an 120VAC charger powered by inverter to recharge LiFePO4 and AGM mix.
Excellent presentation! But I'm confused. I have 2 48v 70 ah lifepo4 batteries connected in parallel that I use strictly for emergency backup. How should I keep these charged properly?
Some of us don't have solar because we live in apartment, so the grid is the only way to charge!
One reason why charge controllers may ask for charging voltage is older LI batteries had a variety of different chemistries and configurations. So the charger is asking what the manufacturer specified.
Most batteries are LFP now and bms have evolved, so they pretty much all operate at the same voltages. But both older chargers and batteries are still out there.
Setting battery state of charge to 20/80 destroys the advantage LFP has over Lead acid.
BMS’s vary, top brand batteries usually also use top end BMS, while budget brands may skimp a bit. Although some budget brands like Redodo and LITime are giving them a run for the money,
It comes down to what BMS features you want and shop around based on that.
With warranties for 3-10 years and charge cycle guarantees of 3500+ cycles it’s hardly necessary to limit charge and discharge ranges. Some confusion comes from older information from different chemistries as well as similar number confusion. (DOD 80% vs 80% capacity after 3500 cycles).
IF, just IF you happen to have or need multiple housebanks, than a bank manager can be useful.
For pretty much anyone else, it’s overkill.
Your LFP batteries will last 10+ years with full daily cycling. Yes they will end up with only 80% capacity by that time, but that a small price to pay. The only reason a 20/80 charge/discharge limitation is good, is because it artificially limits your usage/capacity. If a charge cycle is 100amp, I can’t discharge below 20% and only charge up to 80%, that leaves my usable energy at 60% or 60ah. It would take 2 days to account for a full charge cycle and thereby giving the illusion of a longer life span. You’d also need twice as much capacity to cover your needs, which is what we do with lead acid batteries.
My recommendation is to use the full range of your batteries capacity. If balancing is important to you, get a battery with active balancing build in. Otherwise, you can manually balance the batteries (disconnect and charge individually) once a year.
Battery technology is advancing fast these days. Chances are you’ll replace your batteries after 10 years just to be more up to date. Old batteries can still power a garage or other things.
Lookin' good, Clark! Keep it coming…
You asked if any of us knew of other chargers that use the larger 'information set' that is required to accurately monitor state of charge and acceptance rate of charge. I believe that I saw a video by the developers of the Wakespeed alternator controller that uses a lot of information from the CAN Bus to determine voltage output of your alternator. There is a competitor (not Balmar) that also claims to use sophisticated feedback, but I cannot remember their name. However, these competitors are operating through the alternator, and may not smartly control other inputs like solar panels.
Oh, I got another question… I watched another video where you said that your bank manager won't connect the bank to the lead batteries if there's a significant voltage difference. Suppose you're in the condition that they're disconnected and the lead batteries are supplying a small load. Then some big load occurs (microwave, air conditioning). Is the bank manager fast enough to connect the managed battery bank to the lead batteries as the lead battery voltage drops suddenly? I suppose the answer to this must be "yes"…???
Good video and very nice work on the bank manager. That said, the Victron systems are very good! I have designed, built and used 3 different systems over the last 6 years and have a BS in electronic engineering. The Victron systems can also get you a long and healthy battery life if programmed correctly. I use 13.8v for reset and 13.9v for charge voltage. For my Epoch batteries it puts you right at the level that the battery cells begin balancing if out of balance. The current gradually tapers at 13.9v and the programmed delay time and tail current settings establish the 100% reset. It is very accurate with 99% efficiency setting and 1.01 for Peukert exponent.
I like Clark's LiFePo4 videos. A lot. But they always end up as a Bank Manager sales pitch…. puts me off a little.
Nice Clark! I love listening to these. The deep dive the deep technical stuff. You say you retired from engineering but I think you're still doing a little bit of it. Thank you for doubting it down for us regular folks. That means a lot!
LiFePO4 will develop a memory? Never heard this before. Source?
Some useful information on charging LiFePO4 batteries. However in the real world not everyone has your magic Bank Manager and has to do the best they can with existing equipment.
New batteries are most always delivered with unbalanced cells. If charged at voltages below the balance start voltage, things will get worse, the capacity reduces and the 'weak ' cell gets a hard time thus degrading faster. Typically BMS balance starts at 3.4 to 3.45 per cell, say above 13.6 to 13.8 volts for a 12v battery. Due to the low passive balance current most batteries use, it can take some time, many hours with the voltage above 13.8 volts, for the cells to balance.
With new batteries I recomend using a charge voltage of 14.2 volts, absorbtion period 2 hours, float voltage 13.4 volts. Unless you have Bluetooth or other data access to the cell voltages, that reports cell balance, keep this charge set up for two weeks, ( assuming daily charge cycle). After this period or if cells are reporting good balance at absorbtion volts, a delta of 30 mv maximum, revert to a less agressive charge setting.
A useful low stress charge setting is absorbtion 13.8 to 14.0 volts, absorbtion period 15 minutes , float 13.4 volts.
A factor often overlooked is calibration errors in chargers and volt drops between chargers and battery. Victron chargers can have actual battery temperature and voltage reported over the built in VE buss by the Smart shunt of BMV712 monitor. This elinimates volt drops and allows chargers to stop charging below pre set temperatures.
Where new lithium batteries added in parallel, provided the existing batteries show normal operation and have not been abused, there will be no issues. Normal charge profiles can be used. Any ageing in the older batteries may result in slightly unequal current sharing.
The major 'killers' of lithium batteries are high temperature and holding the fully charged battery for long periods at voltages above its full resting volts, 13.4 for a 12v battery.
I'm an engineer: NASA retired. I listened very closely and critically looking for any errors. I found none. Well done!
Too much BS 😢
Thanks for the great information. Just purchased a used van conversion with lithium batteries so trying to learn all I can.
I, too, read several whitepapers and immediately realized that I needed a better charging system for my lithium – – especially after a low cost charger ruined my e-bike batteries. Having recently purchased / built a Riden bench power supply I realized that the latest firmware update ;provides a very sophisticated algorithm that starts with low voltage constant current (amperage that you specify) and then intelligently switches to constant voltage to the max voltage that you specify. After datalogging the volt & amp curves over time I'm very pleased with how well it follows best practices. Not sure the Riden makes sense as a charger for a marine environment as it is max capable of 60v/16A max and – – more critically – – requires manual intervention to instantiate charging. Perhaps interesting to incorporate their algorithm into a marine system somehow? Thanks for the video Clark. Timely and informative as always.
Can I use two bank Managers on the same lead battery (want to add new lithium to my existing set up).
JK-BMS uses active balancers. Kinda standard BMS in the 16S / 51V world.
Biggest consumer screw up with 12v self-contained LFP battery is not fully charging often enough to balance the SoC on the four series connected cells.
The more the cells get out of SoC balance the lower the available capacity of battery and the greater the likelihood the BMS will prematurely shut down charging due to a single cell reaching full charge before other cells causing it to exceed 3.7vdc maximum allowed cell voltage.
Most BMS's do not do any balancing until a cell gets above 3.4v. You should fully charge to at least 4x 3.5v = 14.0v and hold the 14v for one or two hours to give some time for BMS to do cell balancing. One or two hours held at 14.0v is not a damaging overcharge for LFP four cell battery.
If you do not fully charge LFP for many months, it can get so out of balance it will take many hours held at 14.0v to get battery cells back in balance. For a 100 AH battery, 1% cell SoC imbalance will cause premature BMS charging shut down when attempting a full charge due to an overvoltage cell. Most internal BMS's in 100 AH LFP battery only have a balance bleed current of about 50 mA. To balancing out 1% of 100 AH battery, 1 AH, with 50 mA balance bleed will take 1.0 AH / 0.05 A = 20 hours held at 14 vdc. You want to avoid getting into this situation by keeping up with cell balancing by fully charging at least every couple of months.
Am I the only one who hears Clark’s voice in his head when you read the Bank Manager’s manual? It’s well written but I felt like Clark was sitting in bed next to me reading out loud the whole time I was studying. You’re lucky the dog didn’t wake up and bite you!
"you shouldn't put [different lithium ion batteries] in a parallel bank, but you can put them in separate banks that are in parallel controlled by their own bank manager." HUH?
I only use my trolling motor for maybe a couple of hours each time I fish. Should I top off my two 12 volt the theme batteries or weight until I use them several times.
Great Discussion Clark 👍 I do like AGM Batteries still, as I know for long Service Life, they need to be kept at a minimum State of Charge of 80 % – just adjust the Bank Size accordingly, which means with say an 800 ah bank, the Maximum you can use overnight before Solar kicks in again, is 160 amps from them which Flatlines the RechargeCyclesso they never reduce- which on a Sailbat, for me, is plenty. Then Bank 2 is Lithium Lifepo4 – likely 4 x 230 ah Plus type Batteries, in an overall management role of looking after the AGM Bank, plus engine Start, Generator Start, Windlass and Bowthruster Batteries. so 900 ah, but so the Recharge Cycles for those never fall – according to Ampere Time, which became Li Time – you never let the state of Charge drop below 50 % which means at least 400 amps is available to keep all the other Batteries on the Boat Happy . If sailing between places, then a pretty decent engine alternator, or the Generator, if it is cloudy or Raining, then the Bank Manager will assist in the Lifepo4 Bank Role, by looking after that Bank, by making sure it is looked after properly First, so from the Lifepo4 Bank, DC to DC Chargers look after every other Battery, or mix and match with other Battery managers as well – how best to low stress divide the Workload , is doing my head in at the moment. Top Solution for managing Lifepo4 Batteries is your Bank Manager right now Clark, but the new lightweight Victron DC to DC Chargers may be up to handling AGM Batteries ok for keeping them happy ? 😅 Sorry Clark, I'm not exactly with it right now, a Nurse put compression Socks on both feet, but the one on my Left Foot caused the Skin on my foot to fall off, and the pain killers are driving me a bit DooLally, but at least they are working, and so far so good – No infection. Best Wishes, and Keep Up The Great Work. Bob in Wales. 🤔🌟🌟🌟👍😄
Andy's @OffGridGarageAustralia has wealth of information on charging LiFePo4 batteries, including graphs of the charge/discharge curves, recommendatiins on the 80%-100% maximum charge to 0%-20% minimum discharge, whether to use a passive balancing BMS, whether or not comoression is needed, bulk and absorption charging and how useful a float voltage is. A lot of these apply to these pre-packaged batteries.
You should check out his videos.
excellent review, but i would point out a couple of oversimplification statements made. i have been off grid for past 2 years and have a lot of lifepo4. I do charge it essentially the same way Clark describes, but do not use a bank manager. How, and how do i know? My equipment is SolArk inverters, and SOK batteries, but i monitor with software (Solar Assistant) so i know the voltages and currents in real time. With sol ark at least, but i presume other good inverter/controllers, the chargers are not as simplistic as Clark describes, and have various modes and set points. For example, i use a voltage mode, but i know the voltages exactly because i can watch the hocky stick in real time. i have a large battery bank that keeps the loads low and relatively stable compared with capacity. I set the voltage cutoff at the begin of the ramp, and let it ramp higher once a month. So the small quibble's i have with statements made here are that 13.48 is where the ramps are. Not on mine. different batteries are all a bit different here. The battery mfg should be able to provide values for floats and absorption but a monitor can help you determine this. Also good charge controllers do seem to charge correctly, and i am pretty sure Victron has products that do this right.
On my two Victron IP22 chargers they are easy to program to charge in absorption mode based on tail current. It is not in the base programs but not a problem by going into the advanced settings – expert mode. I think the same is true of most Victron chargers.
Have an older motorhome. Would like to change house batteries to 48V lithium system and keep chassis batteries 12V. Will your bank manager device work with that setup?
You have three Battery Bank Managers for three separate LiFePO4 banks? Does that mean you have three lead acid batteries, paralleled with the three banks? And that the three banks each power distinct circuits on the boat?
Create an international school. (Choose the location very wisely). Then create a license for OFF-GRID LiFePO4 battery technician… installer. Something. Have a course or courses. Entry requires building a certain battery bank with certain capabilities. There could be a list of batteries capable of fulfilling the course requirement. They must purchase your current bank manager, other components such as a voltmeter, weather report and GPS raspberry. You have to write a textbook and sell it also. Add any other text or digital documents and a course logbook. Lead the installer through the setup of the bank, maintenance through varying conditions, heat and cold, add batteries, etc. Whether you pass or not is dependent on the state of the battery bank at the end. The license must be renewed every year with whatever new requirements the industry development create. The value of the license may greatly depend on the abilities of the technicians you produce. But being that each battery bank is like an individual, I think there should be a web base tracker of every battery bank they create also. And that could be used to monitor every battery bank. So a data download raspberry to shoot battery data to the web, when available, could be added. Add how big of a data memory should be added to be able to do this after maybe months being off grid. Be careful of the ability to data exchange though. No one wants a battery bank that could become a bomb or something by a hacker. But the people who can do this properly will be needed. I just do not know the size of that market yet.
Showed up to make a joke about the dangers of Dihydrogen Monoxide.
Stayed for the in-depth talk about battery charging.