commercial solar chrger for lithium-ion batteries

[S.Ahmad]

Hi,
I have a PV project which I have to use the lithium-ion batteries, so I look after a suitable charge controller from a known company.
Does anyone know anything which help me?
Can I use a normal charge controller? (The charge controllers which work with lead sealed acid (AGM or Gel) types)

[Mike90250]

lithium batteries are VERY different from the Lead-Acid batteries, and require a very different charger. A lead acid charger WILL destroy a lithium cell with the first recharge.

All commercial users of lithium have a special charger designed for THEIR use, the batteries are so different from one application to another, they need the charger altered to work properly.

[S.Ahmad]

lithium batteries are VERY different from the Lead-Acid batteries, and require a very different charger. A lead acid charger WILL destroy a lithium cell with the first recharge.

All commercial users of lithium have a special charger designed for THEIR use, the batteries are so different from one application to another, they need the charger altered to work properly.

Thank you mike for your answer, I'd like to know do you know any company which sell proper charge controller for lithium-ion batteries?

[Sunking]

There is only one available from Genasun and it is very limited to a 12 volt battery @ 10 amps.

Otherwise you will have to use controller for Pb batteries and either use external control equipment to make it compatible with Lithium, or buy one that you can set the voltages to be compatible and Bottom Balance the lithium cells.

[donald]

An unknow company would be Electrodacus. He's building a larger model now. Both Victron and Outback are reputed to be workable with Lithium, but not with default settings. Have you been through the compass marine tutorial on pbase? It's sailboat specific, but is applicable to off grid. This tutorial favors top balance on systems with a large number of charge controllers.

You will find a lot of discussion for mains charge controllers for lithium on EV forums. Realistically, to do it with PV now you are going to need to educate yourself. In the end, cost justification can probably only be done assuming a long life compared to LA. But long life is unproven. The best chance for long life, at this point, is probably bottom balancing and keeping max charging voltage at a modest level (depending on brand of battery).

[Sunking]

An unknow company would be Electrodacus.

Stay far away from that idiot. He has been ran off every solar forum and is current getting ripped to shreds on a DIY EV Forum by engineers and scientist. The idiot does not even know Ohm's Law. He is so stupid he claims Ohm's Law does not apply to Solar and Lithium batteries.

[PNjunction]

Can I use a normal charge controller? (The charge controllers which work with lead sealed acid (AGM or Gel) types)

It depends if the controller can DISABLE temperature compensation, and has the ability to set voltages properly.

In my case with small and simple 20 and 40ah batteries made up of only 4 cells, it was easy to charge each one individually to 3.55v upon receipt with a single-cell charger - typically seen as a "3.7v" lifepo4 charger. I pulled the charger when the cell voltage reached 3.55v.

Once initially sanity-balanced, with only 4 cells in each battery, and my needs only <.5C charge/discharge rate, I can get away with a simple Morningstar Prostar-15 PWM controller. HOWEVER, I have *removed* the external temperature-compensation sensor (not all morningstar's work with this removed, but this series does), and set the voltage switch to "sealed". In this Morningstar, that is about 14.1v, which is ok for a 4S battery. (3.525v each cell).

So yes, it can be done, but one must pay proper attention to removing any sort of temperature compensation, have the ability to choose a proper end voltage, and of course start out with relatively closely balanced cells at the top. Top-balancing is kind of a misnomer, but that is covered in other threads.

Basically, you'll want to read up on how to properly operate these cells before spending any money and just bolting things together.

[PNjunction]

Why simple PWM controllers work for me with lifepo4:

Yes, if I was using grid-tie panels, I would need the utility of mppt to handle the higher array voltage.

But, even with garden-variety "nominal 12v" panels, and my 12v application, pwm works at a higher efficiency than it does with lead.

The reason being is that I consider my 12v lifepo4 bank mostly discharged at 80% DOD when the cell voltages just drop to under 3.2v each (12.8v resting). When I use pwm, I am already STARTING out higher in the power-point curve during charge than I would with even a lead-acid at 50% DOD (typically about 12v). That, along with the insanely low internal resistance adds up to high efficiency - at least much higher and faster than you obtain with lead. For most of us, time is not usually on our side with solar.

So while an mppt controller is definitely needed with grid-tie panels, my use of pwm (appropriately set and temp-comp disabled of course), and nominal 12v panels (18v ocv), I don't feel the absolute need to go with the advantages of an mppt controller - at this time.

So choose wisely, but if pwm is all you have, just know that at least on the whole, it is more efficient than charging lead.

[JKFlipFlop]

Guys, wouldn't using Zener diodes of the correct voltage be a great way to allow any charge controller to be used on lithium batteries?
Just use a 14V Zener diode (in reverse bias obviously) from the positive lead of the battery bank to ground to act as a voltage regulator?

[Mike90250]

Guys, wouldn't using Zener diodes of the correct voltage be a great way to allow any charge controller to be used on lithium batteries?
Just use a 14V Zener diode (in reverse bias obviously) from the positive lead of the battery bank to ground to act as a voltage regulator?

And you forgot the wattage requirement of the diode, which will have to disaipate the entire 800W array power when the batteries are full.

Many high end commercial chargers have programmable set points, and that would work fine, set the absorb to your high voltage limit, and just for 1 minute.

[Sunking]

Many high end commercial chargers have programmable set points, and that would work fine, set the absorb to your high voltage limit, and just for 1 minute.

Actually easier than that. Set Bulk-Absorb-Float to 3.4 to 3.5 vpc and forget about it on a Bottom Balanced pack.

[Gajetest]

Lots of choices

Hi,
I have a PV project which I have to use the lithium-ion batteries, so I look after a suitable charge controller from a known company.
Does anyone know anything which help me?
Can I use a normal charge controller? (The charge controllers which work with lead sealed acid (AGM or Gel) types)

Hi, I'm Gajetest we are not open for business yet although I have been writing a blog since January and we are about to launch our store. However, after reading the post you ask a simple question and I didn't see any simple answers. We in America due to special interest like trying to keep the inevitable death of the Power Company from happening (they're own prediction is 10 to 15 years) One way was to ban Grid-Tied solar systems in one state that uses the most solar power in America that being Hawaii according to Scientific American when they published an article saying the power companies stance that fluctuating Solar power was harming the Grid was malarkey.The only thing Solar power was doing was cutting into their bottom line.

As for your question the average charge window for solar panels is 4 to 5 hours a day if you are lucky. I use dual axis suntrackers so I get more, but that's me. Average 4 person home uses 16.5 KWH in a 24 hour cycle. I have a 48 volt system as it is the voltage for stable output to your inverter. I also use a 12K inverter. My solar charger I use a hybrid system so had to go with two controllers. You can charge a LiFePO4 at over 100 amps and it will not do as some say blow. I found a site that has a really good looking 24 volt LiFePO4 he put a BMS on every string of cells.

China's electrical Grid infrastructure sucks. So they are in their industrial phase and had to come up with the best equipment to get the most out of the resources they have as China is a very large country. Solar, Micro-Hydroelectric, Bio-fuels that have close to zero emissions. And my personal favorite lots of Solar , wind controllers that will deliver the most amps during your charging window. You do not want your system to be not sucking up that sunshine using a trickle charge like a lead acid does. You need your battery bank to be sucking up amps like a camel sucking up water at a watering hole. That means you can charge with over 100 amps if you want.

All lithium technology prefers two stage (constant current followed by constant voltage) charging.I have a new pack on order that is 15 3.2 volt 1000ah which will give my hybrid system 48 KWH backup power. I know I cannot use it all and not damage the battery bank. But just the controller and my bank is all I need the controller is adjustable. I'll never run out of power with the technology we have today right now. Plus, have different systems setting around to test one generator uses wood pellets for fuel or actually anything organic that will burn like seaweed, peanut husk etc. They're many controllers out there that will charge LiFePO4's all these batteries ask is a constant voltage and amperage, and don't float charge them unless you are using them while you are charging them. Take a look at the link I have nothing to do with it it was just a great looking set-up and the guy really knows what he is doing he even put a BMS on every string of cells for extra safety, and shows them with thermal imaging on to show their temperature when he is charging them. Oh and they don't cost as much as people say as long as you don't buy outback. What makes Outback so great is the redundancy of their safety system, meaning they can take a beating. But you can buy Solar controllers that will charge your LiFePO4 battery bank from $250 and up. Or really you can just keep an eye on it and if your controller has MPPT on it and I'd probably put a BMS on it then, but that will work for really inexpensive setup.