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Charge controller recommend
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02-04-2021 7:16pm#1
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What specific gravity do Victron charge a lead battery to?
In terms of reliability do they solder their input fuses on their inverters?
Do their temperature sensors work accurately with live feedback?
Does their hardware run for a decade continuously? What's their product failure rate?
Why are there harmonics on this inverter with no other load?
Which one of these meters would you say is more truthful?
How much of the product's pricetag is marketing and how much is hardware?
Regarding the App...the expression foxes guarding the henhouse comes to mind.0 -
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I just took a moment to look at a Victron product.
..They're all like this!
How can you supply a 120A continuously rated product on 50A continuously rated cable and not get sued?
I bet it has something to do with the product not being capable of doing 50% rated to jeopardise the installation.0 -
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I'm not arguing just sharing experience.
I run an Albright SW80M magnetic latching contactor for split charge and I can get 80A across that. It cost me £30 + shipping.
I also have a Sterling B2B 120A which does a slightly better job.
I've fitted 120A B2Bs and got less than the contactor which is rather disappointing comparing a €600 product to a £30.
I don't entertain ideas of split charge less than 50A
I'm putting twin 100A linked alternators in my truck and I plan to get 150A at idle from both @ 24v without any boost regulator boxes.
Regarding chargers if it's not charging to specific gravity 1.275 then it's harmful to your battery. Most don't. Victron are certainly better than factory fitments.
The biggest problem with most chargers is the temperature compensation being inaccurate or not present. It has to be remotely sensed and heat sinked to the battery.
Victron moved from measuring the charger temp locally to recently measuring the air temperature around the battery via bluetooth.
The BMV is too small to read, the blue backlight is naff, the backlight controls are way too complicated, the SOC ceiling is patronising.
Their chargers heat derate quickly too.
There is no 100% accurate SOC meter.
Smartgauge is good but 10% lies.
TriMetric is the best I've found in my opinion.
Studer are ok also small.
I haven't tried Xantrex which everyone else clones.
Mastervolt is very poor.
Don't let it be said that I'm picking on Victron...
Mastervolt are shockinly bad for the price.
Sterling Power performance is good, price is excessive and the build quality is extremely low.
ProNautic are good.
Ctek Auto are poor, Ctek Marine are good.
Steca are woeful.
Xantrex are mediocre.
Midnite & Outback are ok.
EP Solar is value for money.
The thing that annoys me about Victron the most is the disparity between the promise and the delivery....
....and how when people are buying chargers they are sold on an app more than it's effective capability.
I've never replaced a lead acid battery I bought new that I put on a MorningStar controller.
My oldest is 6 years although I have 10 year olds that I recently adopted and are working perfectly.
There's two important details people never seem to mention when recommending chargers.
One is specific gravity attained...this is the most accurate test.
The other is the effective capacity of the battery after one round trip compared to a control (from specific gravity 1.275)
I think most people are reviewing the ease of install, features and marketing.
Personally I don't think installations ought to be interactive with a phone. Phones break, get lost, aren't waterproof mostly, batteries run out, security issues, they're pretty cumbersome interfaces, they're expensive in terms of liability etc..0 -
Sir Liamalot wrote: »The BMV is too small to read, the blue backlight is naff, the backlight controls are way too complicated, the SOC ceiling is patronising.
I guess victron trying to replace BMV with smart shunt solution.Sir Liamalot wrote: »I don't entertain ideas of split charge less than 50A
I think 30A split charger idea not to overburn alternators see test
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I guess victron trying to replace BMV with smart shunt solution.
That would make it cheaper to manufacture. Is it the same price as the BMV?I think 30A split charger idea not to overburn alternators see test
That's this new thing the hilarious irony of promoting li-ion that due to the charge acceptance rate and comparative voltage they very easily force the alternators to full field and hold them there.
So we're first sold batteries with a high charge acceptance (if they are maintained at 10°C > 30°C) and then sold expensive boxes to limit the charge power and expensive chargers that derate in the cold to stop the battery igniting.
How do we stop alternators melting? Make it Sh1t!....spare me!
Get a decent Bosch alternator that can withstand 120°C case temperature.
Get an external temperature proportional regulator or a 50Ω potentiometer.
Water cool your alternator.
Get twin alternators.
Don't waste your money on silly expensive batteries and then derate the system to use them.
Why are the comments turned off on the Victron Channel?
Most alternators are air cooled by a driving headwind proportional to the speed you are doing.
30A...psah!
Li-ion...charges faster...more efficient! Needs a system derating....and battery heaters...and chillers...half the weight...4 times the price...same life expectancy...has a memory effect...damaged by PWM solar controllers....requires a BMS...BMS often damaged when you plug in an inverter...damaged by float charging....no off the shelf suitable chargers...best stored empty...does not like being held at high SOCs...makes your chargers derate according to SOC and temperature....:rolleyes:0 -
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That burned out the rectifier not the coil Victron....good journalism...
....seeing as I'm correcting their homework; it's not accepting more charge because the internal resistance is lower, because it's nigh the same internal resistance as lead. It's accepting more charge because it's fully charged at 13.6V which is signalling to a lead acid designed alternator regulator to open the field because that's an extremely low SOC for a lead battery under charge.
The measured efficiency difference between li-ion and lead is 2% without thermal management on the li-ion and below Specific Gravity 1.27 for the lead0 -
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You know that thing they say that you have to charge a lead-acid battery to 100% every week to reverse potentially harmful chemistry?
Well due to this efficiency curve,
That's extremely hard to do. So most manufacturers don't bother because only anoraks like me test them and notice. Everyone else replaces their battery every coupla years and thinks that's normal.
1.265 is what most expensive chargers will attain.
If it weighs more that 1kg and came with the camper coach build 1.24 might be the best you can hope for.
It also displays the non-linearity to this 80% efficiency claim that people use to promote li-ion that is in practical applications irrelevent.
MorningStar are the only charger I have ever found to break through the inefficiency belt and charge to 100% SOC or specific gravity 1.28.
Even Studer can't do it.
The upshot of which is I run a charge fully once a month regime and 60% DOD.
You can drop lead-acid to 20% SOC / 80% DOD and it'll cost about the same. Double the energy half the cycles.
...but first you derate 10% for climate, 10% for age, 10% for your charger only going to 90%, 10% for the manufacturer over-rating said battery, and 10% for overhead because less than 20% SOC is extremely harmful.
The difference between the high-end chargers and the rest isn't power, it's partially energy but mostly reliability and battery longevity.
...and accurate, live feedback, remotely sensed heatsinked temperature sensing. Seriously that's important. Temp sensing is where most falter first.
You know how to get better C-rates and higher capacity from lead than lithium for a fraction of the cost?
Get flooded golf cart batteries, dial up the chargers to 14.8V + temp comp, now your electrolyte is coolant so install hydrocaps...
Maintenance Shedule: You put one end of the tube in a bottle of water, thuther onto the battery quick connect hose and squeeze it 5 times twice a year.
Presto
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That would be an advantage for lithium lifepo4 batteries not require charge to 100%. : )
LiFePO4 has a memory effect you do need to charge them to 100% or you'll get ever diminishing returns on capacity. You won't find an LFP that doesn't because plotting a 20% - 80% usable aperature is so difficult with a flatline holding voltage, the short-lived outtov box performance is good for credibility until it isn't and the implementation of cheap parasitic passive balancers require it or they are not balancing but still acting as permaloads. You can't turn most BMS off either. So if you leave a vessel unattended you have to ensure you don't leave it charged, don't leave it charging, don't leave it empty and make sure you charge it before the BMS destroys it.
Any overcharge whatsoever is harmful often terminally so...in contrast look at the lead efficiency graph and explain why I ought to be concerned about overcharging lead..is it even possible with a modicum of regulation? Every time the sun rises on your solar panel with a charged LFP battery it's doing permanent damage. They do not like float charging or being held in absorption/float for load compensation. So they're a terrible choice for solar applications.
In fact, any application where you rely on a generator to supply power instead of a battery...ie. most of them.
Mains chargers, wind and alternators are a problem too because they'll hold a float.
Then there's temperature issues. The can't be charged in the cold. They range from being permanently damaged if charged below 10°C at a high rate to outright self-combusting if charged below 0°C.
They are exothermic, using them releases heat. If they get above 30°C they are being damaged and they will do this with heavy sustained loads and charging.
In lieu of all these factors and more, people are implementing stringent measures to limit charge and discharge to rates far below lead-acid's capability.
People are adding active thermal management with a parasitic loss far in excess of the comparative inefficiency of lead-acid.
Then there's the cost. You can buy 4 times the capacity of lead-acid than you can of LFP including BMS. This means you have greater range and reserve with Lead-acid and equal charge and discharge rates except lead -acid doesn't derate charging and loads.On a build your self basis, Lithium cells grade A with bms Bluetooth monitor 270AH (usable ~ 250AH ) can be done for less than 700e
How many fully working reliable systems have you built for that price?
Providing that AGM discharge shouldn't be below 50% max.
80% and AGM are extremely expensive anemic batteries with the exception of oasis firefly that are extremely expensive. Flooded golf carts are twice as good.we would need 500AH AGM battery bank to compete with lifepo4. + More weight and space has to be allocated.
Lead acid you can cycle 100% to 20%
LFP ideally 80% to 20% with periodic memory releasing cycles to 100%.Also higher discharge rates wouldn't matter much for lifepo4 as it would for AGM.
How so? You can get three times the lead for the same price as lithium. So you can charge/discharge a 600Ah Lead at 100A, or a 200Ah LFP at 100A. Which is higher?So with lifepo4 I can opt out of gas and run induction cooktop, microwave, laptop, tv, all at the same time worry free : )
Why can't you do that with lead?0 -
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Double the cycles, double the life expectancy, half the price, you can drive them like bejaysus because the electrolyte is a replaceable consumable aka an evaporative coolant.
Oasis fireflies are the fulfilled promise of LFP marketing, delivered in a lead format.
If you want the best then look for OPzS tubular lead. 2V cells. Best value by the ton.
Did I mention it takes me two weeks to program an LFP charge algorithm on an installation?
Here's a guy smarter than I am and more dedicated to LFP technology...even he's struggling to do it. The man built a sonar anti-foul and the battery management is taking years to complete.
AGM was the expensive better thing marketing loved to push before li-ion came along. Same shovel different sh1*.0 -
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Thats what I mean, when you said in previous posts that AGM like to stay at 100% vs Lithium not of that nature. You might charge battery to 100% time to time to clear memory effect.Sir Liamalot wrote: »Lead acid you can cycle 100% to 20% LFP ideally 80% to 20% with periodic memory releasing cycles to 100%.
I don't know where you get that AGM can be discharge to 20% without being damage.
here is the chart AGM vs Lithium discharge voltage
Sir Liamalot wrote: »However, any overcharge whatsoever is harmful. Every time the sun rises on your solar panel with a charged battery it's doing permanent damage. They do not like float charging or being held in absorption for load compensation. So they're a terrible choice for solar applications.
In fact, any application where you rely on a generator to supply power instead of a battery...ie. most of them.
For that reason victron MPPT charger Bluetooth app incl. settings for Lithium battery, + adjustment of float voltage & time.Sir Liamalot wrote: »Then there's temperature issues. The can't be charged in the cold. They range from being permanently damaged if charged below 10°C at a high rate to outright self-combusting if charged below 0°C.
10°C perfect charging temp. for lifepo4 battery but agree on when Battery temp. below 0°C hence good BMS comes with temperature sensor to prevent potential damage.
There no perfect battery but at list we have choice that works better for one application or another.
Here is the limitation of AGM batteries
-Low energy density - poor weight-to-energy ratio limits use to stationary and wheeled applications.
-Cannot be stored in a discharged condition - the cell voltage should never drop below 2.10V.
-Allows only a limited number of full discharge cycles - well suited for standby applications that require only occasional deep discharges.
-lead content and electrolyte make the battery environmentally unfriendly.
-Transportation restrictions on flooded lead acid - there are environmental concerns regarding spillage.
-Thermal runaway can occur if improperly charged.Sir Liamalot wrote: »They are exothermic, using them releases heat. If they get above 30°C they are being damaged and they will do this with heavy sustained loads and charging.
where you getting that information from?
See chart below
What about AGM?
The optimum operating temperature for the lead-acid battery is 25°C. Elevated temperature reduces longevity. As a guideline, every 8°C rise in temperature cuts the battery life in half. Good AGM, which would last for 10 years at 25°C, would only be good for 5 years if operated at 33°C. The same battery would desist after 2½ years if kept at a constant temperature of 41°C
Here is the chart
Sir Liamalot wrote: »The lead-acid performs well on high load currents.
Disagree, what about Peukert exponent?
The faster a lead-acid battery is discharged, the less capacity it has. The effective battery capacity therefore depends on how deep you can discharge a battery, and how much energy is lost due to the speed of discharge of your battery.
You can buy higher AH AGM batteries but the usable AH only stands at ~ 50% of that + heavy weight and space that requires.Sir Liamalot wrote: »Then there's the cost. You can buy 4 times the capacity of lead-acid than you can of LFP including BMS.
Basic BMS with 100AH discharge cost no more than 30e
270ah lifepo4 cells cost 400e as we speak
I am not professional, I think you have deeper knowledge on the subject and I am hopping that I can learn some more : )Sir Liamalot wrote: »How many fully working reliable systems have you built for that price?
But prismatic cells that I have mention only couple of companies manufacturer in Asia
And I have see these cells being used by many companies incl. top brands sold for 1300-2000e as complete battery in nice shiny "professionally looking" plastic boxes.
Sir Liamalot wrote: »Why can't you do that with lead?
When running inverter 3500w on AGM the voltage drops below usable means on lithium I have far steady voltage and be able to use more appliances same time. And chart again 0 -
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Compare AGM vs LifePo4 battery
Lithium – Discharge Capacity vs Terminal Voltage
Lead Acid – Discharge Capacity vs Terminal Voltage
Usable Energy (Lead Acid)
Usable Energy (Lithium)
The recommended charge rate for large size AGM batteries is 0.2C i.e. 120A for a 600A battery consisting of paralleled 200Ah blocks.
Higher charge rates will heat up the battery (temperature compensation, voltage sensing and good ventilation are absolutely needed in such a case to prevent thermal runaway), and due to internal resistance the absorption voltage will be reached when the battery is charged at only 60% or less, resulting in a longer absorption time needed to fully charge the battery.
High rate charging will therefore not substantially reduce the charging time of a lead-acid technology battery.
By comparison a 200Ah Lithium battery can be charged with up to 500A, however the recommended charge rate for maximum cycle life is 100A (0.5C) or less. Again this shows that in both discharge and charge that Lithium is superior.
Clearly AGM batteries will need to be replaced more often than Lithium. It is worth bearing this in mind as this entails time, installation and transportation costs, which further negates the higher initial capital cost of Lithium as does the lower cost of recharging Lithium.0 -
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Sir Liamalot wrote: »Did you notice they were branded Chinese Aviation Lithium Battery? CAM 72...one of the best thermal designs. Aluminium case with stack spacers.
1C is aggressive.
Deligreen Genuine reseller.
Interesting. calb cells usually more expensive. I have purchased from aliexpress Eve cells.
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They're based on controlled cycle tests in a laboratory. The only purpose of them is to be compared to other batteries cycle tests in a laboratory.
I can show you batteries the user has killed in less than 20 cycles or ones that have been in use 5 years every day still ticking 100% and only clocking less than 200 cycles to 50%.
True story:
After using an FLA battery in a van as a 6-month annual full-time liveaboard for 5 years I ascertained from my collected data I was effectively on < cycle 180 to 30% DOD.
11300Ah Extracted
That leady battery oughta last me another 55 years so!
Batteries hardly ever meet a natural end. Users and bad chargers usually do them in way before it.
Don't worry about cycles other than to compare a purchase.0 -
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10°C perfect charging temp. for lifepo4 battery
Lithium plating....it's a huge problem. The electrons travel faster than the li-ions when charging in the cold and that causes irreparable cell damage.
Problem threefold. I need a 3rd party alternator regulator to derate my charge system in the cold and/or normal operation, or a battery heater which is appallingly inefficient, or the latest brainiac mentioned something about engine frickin' coolant loops...:rolleyes:
The battery is so expensive it's likely to be small so the C-rates are high by nature.
Then I need the alternator, solar, mains etc to not operate if the battery is fully charged or has been recently.
Threefold problem the second:
In order to integrate a very small and expensive battery to a 12v system, we need an expensive BMS and high-end chargers that are highly programmable to orchestrate the process.
I can get 80% from lead. I can get 80% from LiFePO4.
Lead is one third the cost (before the LiFePO4 required electronics to derate the system are factored) & double the weight.
Now if this is my SOC envelope:
Firstly: the voltage variation in 20% SOC and 80% SOC is so narrow only the top shelf chargers are accurate enough to measure this. If it hasn't got remote voltage sense terminals then it hasn't a chance.
Secondly there's effectively no bulk stage because that is triggered as being ~0.5V under absorption voltage. So instead chargers go instantly to CV absorption and my "fast charging" lifepo4 (in 20°C...which it never is) takes a full day to charge because the charger is locked in constant voltage.
If I want to use constant current instead I need to use over-voltage and tail current which limits me to chargers in the > €250 class.
If I try to operate within that aperture I get diminishing returns from memory effect because the absorption cutoff becomes a moving target.If I try to charge to 100% to avoid this I get long-term reduced cycle capacity.
All this for a fraction of the capacity lead can offer for equal expenditure.0 -
I made a graph of that
Popular belief would have one believe
Bad < 0°C < Good
Taking my lesser camper as an example. If I threw away my FLA battery and got one under half the capacity for over twice the price, if I limit my alternator to 50% it's current output then I can use a "faster, more efficient" variant about 3 quarters of the year...where do I sign up?
PS I use the most aggressive charge rates in Winter..go figure!
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