Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rating: Thread Rating: 33 votes, 4.82 average. Display Modes
Old 25-02-2015, 14:56   #4291
Registered User
 
bill good's Avatar

Join Date: Oct 2006
Location: Brisbane Australia
Boat: Crowther windspeed 36' cat Goldrush
Posts: 700
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Just installing 300 ah (CA100X3) & they exceed the specs. Test results to follow

regards Bill
__________________

__________________
bill good is offline   Reply With Quote
Old 25-02-2015, 15:33   #4292
Marine Service Provider
 
Maine Sail's Avatar

Join Date: Jan 2007
Location: Maine
Boat: CS-36T - Cupecoy
Posts: 2,902
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Quote:
Originally Posted by bill good View Post
Just installing 300 ah (CA100X3) & they exceed the specs. Test results to follow

regards Bill
They usually do.. I am going to guess 106% - 108% of rating...
__________________

__________________
Marine How To Articles
Maine Sail is offline   Reply With Quote
Old 26-02-2015, 09:33   #4293
Registered User
 
SailorGerry's Avatar

Join Date: Dec 2014
Location: Gig Harbor, WA (now in La Paz)
Boat: Jeanneau 45.2
Posts: 37
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Quote:
Originally Posted by autumnbreeze27 View Post
I need to replace my main battery bank and am considering a Balqon 5 kWhr pre-fab solution. Any reason not to go this route? I'm close enough that I can drive over and pick it up with my truck.
You would want to have some level of confidence that Balqon will be around if you had a warranty issue. Industry rumors are that they are struggling. I couldn't even get them to respond to my emails or phone calls 2.5 months ago. Recommend you proceed with "due diligence".http://www.cruisersforum.com/forums/...ies/danger.gif
__________________
SailorGerry is offline   Reply With Quote
Old 26-02-2015, 09:40   #4294
Registered User
 
Highland Fling's Avatar

Join Date: Mar 2007
Location: Sunny Scotland but sail in the Caribbean
Boat: Beneteau Oceanis 461
Posts: 369
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

WELL we have DUN IT.

I had delivered yesterday to St Martin 30 Winston Thundersky 200A Wide cells.

Looking at the cells as delivered and measuring the voltages they are 90% sitting at 3.25V with three at 3.2V.

I am going to top balance them and have a Lab Power Supply to do this with. I am probably going to charge to 3.7 or 3.65 volts..Any thoughts on this?

I had to buy boxes of ten and I will use 16 at most so 'might' have a few to sell - maybe even with the Australian BMS/Cell Modules.

Not yet sure of the configuration but thinking of having up to 800AH either in four 12V/200AH or two 12v/400AH 2P4S batteries - as a minimum - three 12v/200AH - Just like flying Triple Redundancy .

After much looking around I am going to be using an Australian BMS and Cell modules

EV Power - Australian Electric Vehicle Specialists — EV Power - Australian Electric Vehicles sells Electric Bikes and car conversions, Electric Bicycles, Electric Vehicles, Conversion Kits.


I did have a look see at the Slovac BMS system but it looks TOO FEATURE RICH for what I want.....I will use some R/C LIFEPO Battery Cell monitors to give me any instant cell measuring and battery state info as well as some alarms.

RC Cell Log 8M Cell Voltage Monitor 2S 8S LiPo | eBay

1 8S LiPo Li ion FE Battery Voltage 2in1 Tester Low Voltage Buzzer Alarm Fo | eBay


I am probably going to have only one bus bar as I really cant see how I can generate an Over-Voltage Situation with my present charging equipment and have a HVC and yes I do understand that a HVC is a cell over-voltage situation and could happen even if I don't have an OVS on the charge side of the bus.


Seems I have to change my solar controllers so I get a single stage constant voltage charge and not the two stage one I have ATM as my controllers are set for GEL/AGM But for now the present LA charge system will do until I have more hands on experience

I will also need to look at upping the engine charging capacity as well, probably change the DR 10SI 80A to a DR 12SI 170A and may even fit two (another alternator), though I don't expect the engine to be my main/normal source of recharging my house bank, that is going to be 840W of solar 6 x 140W Kyocera panels and a 'suitable controller.

Reading some stuff online with folks living on solar they say a PWM controller will outperform an MPPT every day of the week, that suggestion seems to be at odds with what the manufactures says....QUELLE SURPRISE.

Thoughts Ideas Advice....welcome

MORE SOON including some pictures I hope

Kindest regards

David
__________________
Highland Fling is offline   Reply With Quote
Old 26-02-2015, 10:39   #4295

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 12,112
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

"they say a PWM controller will outperform an MPPT every day of the week,"
I doubt that's physically possible, David. It would, however, be easy to get that impression if someone wasn't aware of all the issues.


First, there are fake MPPT controllers coming out of China. They say MPPT, they apparently aren't, so folks who use them will see no improvement. Second, you'd need both ammeter and voltmeter, in the live circuit, to see the real difference. And then of course every MPPT maker has their own proprietary charging scheme, unless they've just bought one of the new chips and done a "me, too!" of varying quality.


When I tested a BlueSky controller some years ago, I was expecting to see a conventional three-stage charging profile. Uhuh. The controller uses a microprocessor and a look-up table along with user programming. IF you have read the instructions and IF you have programmed the battery specs correctly, the controller *constantly* is supplying a slightly higher voltage than the batteries are at, at maximum amperage. So you may literally see 12.2v output from the controller to the batteries, when you are expecting 14.4 on the bulk charge. Once the battery gets charged a little higher, the controller steps up the voltage, maybe to 12.4, then 12.5, then 12.6, until it does go to full bulk charging voltage. But if you just stick a voltmeter in once, all you will see is that first low incremental voltage, with no idea of why it is "too low".


All of the reviews, all of the techs, all of the sources that have actually explored real MPPTs and tested them, agree that they will give you some 10-20% more power during the course of the day. The only things they disagree on are the exact amount of the boost (it varies) and the exact loss of the controller (typically 2-4%, still leaving a 10-20% net gain).


Whether they are worth the price for a possible 15% net gain? Depends on your situation and your options. But saying they don't work and work better, is like repeating that the bumblebee can't fly because it doesn't have the right lift-to-drag ratio. It just proves you haven't measured all the real factors.


12V panels may be producing 17-22V at peak output. 12V batteries can't use that voltage, so basically all the power produced by the high voltage is dumped and wasted by PWM controllers. Dumped. Versus an MPPT controller, which uses all of the extra voltage, converting it to extra amperage which will be used instead of wasted.
__________________
hellosailor is offline   Reply With Quote
Old 26-02-2015, 13:53   #4296
Registered User
 
Highland Fling's Avatar

Join Date: Mar 2007
Location: Sunny Scotland but sail in the Caribbean
Boat: Beneteau Oceanis 461
Posts: 369
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

I would tend to agree with you BUT I will get the URL of the thread and you an see what they are saying....... and they are talking about real world performance not just hanging on a DVM.

kindest regards

David
__________________
Highland Fling is offline   Reply With Quote
Old 26-02-2015, 14:28   #4297
Registered User
 
Highland Fling's Avatar

Join Date: Mar 2007
Location: Sunny Scotland but sail in the Caribbean
Boat: Beneteau Oceanis 461
Posts: 369
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

PICTURES









__________________
Highland Fling is offline   Reply With Quote
Old 26-02-2015, 15:05   #4298
Marine Service Provider
 
Maine Sail's Avatar

Join Date: Jan 2007
Location: Maine
Boat: CS-36T - Cupecoy
Posts: 2,902
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Quote:
Originally Posted by hellosailor View Post


When I tested a BlueSky controller some years ago, I was expecting to see a conventional three-stage charging profile. Uhuh. The controller uses a microprocessor and a look-up table along with user programming. IF you have read the instructions and IF you have programmed the battery specs correctly, the controller *constantly* is supplying a slightly higher voltage than the batteries are at, at maximum amperage. So you may literally see 12.2v output from the controller to the batteries, when you are expecting 14.4 on the bulk charge. Once the battery gets charged a little higher, the controller steps up the voltage, maybe to 12.4, then 12.5, then 12.6, until it does go to full bulk charging voltage. But if you just stick a voltmeter in once, all you will see is that first low incremental voltage, with no idea of why it is "too low".

Bulk is not a voltage it is the constant current phase of charging. Solar controllers are CC/CV charging devices. Bulk = CC and Absorption = CV.

You are confusing bulk/CC and absorption/CV charging. Would not be your fault because some marketers have bastardized the terms for marketing purposes and to confuse and dumbfound those who don't understand how CC/CV charging works.

Solar can only raise the battery terminal voltage at a rate the current can be supplied and creep it up. Solar on boats it is significantly slower than an alternator or other high amperage source unless you had a massive array...

You don't apply 14.4V to a battery and the battery terminals magically jump there. You apply a current source and the voltage slowly rises to absorption or constant voltage mode (CV) where the controller now limits voltage.

With a small solar array it can often take days of bulk charging to get out of CC/bulk. With a decent sized array you may attain a limiting voltage (CV) in 4-6 hours but it really all depends on how much current the array can provide and the SOC the battery was at when you began charging it...

The voltage regulators, battery chargers and solar controllers we use in the marine market are all CC/CV and in CV mode all they do is limit the voltage to the preset maximum.

In bulk they are not yet at a voltage to limit so the source provides all the current it can or CC.... If your batteries jump to 14.4V once a charge source is applied your batteries have major issues....
__________________
Marine How To Articles
Maine Sail is offline   Reply With Quote
Old 26-02-2015, 15:12   #4299
Marine Service Provider
 
Maine Sail's Avatar

Join Date: Jan 2007
Location: Maine
Boat: CS-36T - Cupecoy
Posts: 2,902
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Quote:
Originally Posted by Flying Scot View Post
I would tend to agree with you BUT I will get the URL of the thread and you an see what they are saying....... and they are talking about real world performance not just hanging on a DVM.

kindest regards

David
How about real world head to head into an actual LiFePO4 battery.....

MPPT vs. PWM - LiFePO4
__________________
Marine How To Articles
Maine Sail is offline   Reply With Quote
Old 26-02-2015, 15:36   #4300

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 12,112
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Maine-
You make a good point. Modern chargers aren't like the old antiques that were simply voltage regulated and put out all the amperage that their transformer, and the battery's state, would allow. It might be more correct to say the MPPT controller will restrict voltage to the lowest level the battery will charge at, while maximizing amperage. No?
IIRC a manufacturer said to me that any voltage which is higher than the minimum necessary, does not really charge the battery it just boils (micro bubbles) electrolyte in a wet lead battery, gets wasted as heat if it can't do that, but that for effective charging the old "3 stage" logic is obsolete, and maximizing amperage is the best way to go. Which is the MPPT way.
The unique voltage curves in lithium being just one of the many considerations that make them different. They've only been around for what, 98 years now? And they're still being figured out?
__________________
hellosailor is offline   Reply With Quote
Old 27-02-2015, 06:14   #4301
Registered User
 
transmitterdan's Avatar

Join Date: Oct 2011
Boat: Valiant 42
Posts: 3,140
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

MPPT has nothing to do with the battery. MPPT is a technique to get as much power as possible out of the PV array. A PV array transfers maximum power at a certain voltage and current which changes as sunlight varies Almost never is this the voltage or current the battery needs at that moment. So a MPPT controller adjusts the current draw from the PV until it finds the maximum power condition. Then it outputs whatever current the battery will take in CC or CV mode. This technique will charge batteries faster because more joules can be drawn from the PV per hour and efficiently delivered to the battery.
__________________
transmitterdan is online now   Reply With Quote
Old 27-02-2015, 11:03   #4302

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 12,112
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

"MPPT has nothing to do with the battery."
Really?
Because a good MPPT controller is programmed with the battery's capacity (Ah) as well as the battery type and specific voltage, and the MPPT will be actively looking at the battery charge state while it is independently converting the solar output to the specific charge the battery can best benefit from.

I'd call that having everything to do with the battery.

Yes, the MPPT controller is adjusting the load on the solar panel/array to draw the maximum available power out of it, by one of several schemes. But that's half, at best, of what it is spending it's time doing.

What it DOES with the power it has gleaned from the panel(s) is just as complex and important as how it gets that power. It is very much an interface between two pieces of equipment, and it has to do with the specifics of both of them.
__________________
hellosailor is offline   Reply With Quote
Old 27-02-2015, 11:09   #4303
Registered User
 
NahanniV's Avatar

Join Date: Mar 2011
Location: On the Boat
Boat: Finnsailer 38
Posts: 1,027
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Quote:
Originally Posted by NahanniV View Post
28-01-2013 Better than advertised !

Just finished my load test:

411AHA over 20h16m
Lowest cell: 3.09V
Maximum cell difference: 50mV
Lowest pack voltage: 12.41V

2013 Test:


....
After two seasons of very light usage I just completed a capacity test on my 12v 400AH 4S Winston LiFePo4 2009vintage cells.

I did not charge the cells as aggressively as I did in the previous test 3.5VPC vs. 3.7VPC. I just brought the pack up to 14.0V and did some minor balancing (first adjustment since initial).

The results:
330AH over 17h
Lowest Cell: 2.98
Maximum cell difference:100mv
Lowest pack voltage:12.05V

The cells have clearly lost capacity since my first test.

Cheers,
JM
Attached Thumbnails
Click image for larger version

Name:	2015test2 (2).jpg
Views:	103
Size:	287.7 KB
ID:	98005  
__________________
NahanniV is offline   Reply With Quote
Old 27-02-2015, 11:12   #4304
Registered User
 
transmitterdan's Avatar

Join Date: Oct 2011
Boat: Valiant 42
Posts: 3,140
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Quote:
Originally Posted by hellosailor View Post
"MPPT has nothing to do with the battery."
Really?
Because a good MPPT controller is programmed with the battery's capacity (Ah) as well as the battery type and specific voltage, and the MPPT will be actively looking at the battery charge state while it is independently converting the solar output to the specific charge the battery can best benefit from.

I'd call that having everything to do with the battery.

Yes, the MPPT controller is adjusting the load on the solar panel/array to draw the maximum available power out of it, by one of several schemes. But that's half, at best, of what it is spending it's time doing.

What it DOES with the power it has gleaned from the panel(s) is just as complex and important as how it gets that power. It is very much an interface between two pieces of equipment, and it has to do with the specifics of both of them.

The MPPT part doesn't know anything about the battery. That's a different system. MPPT just concerns itself with the PV array. It's job is to draw maximum power from the PV array until the battery charger part needs less power than the PV is making.
__________________
transmitterdan is online now   Reply With Quote
Old 27-02-2015, 11:50   #4305
Registered User

Join Date: Jun 2007
Location: SW Florida
Boat: FP Belize, 43' - Dot Dun
Posts: 3,025
Re: LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

Quote:
Originally Posted by hellosailor View Post
"they say a PWM controller will outperform an MPPT every day of the week,"
I doubt that's physically possible, David. It would, however, be easy to get that impression if someone wasn't aware of all the issues.


First, there are fake MPPT controllers coming out of China. They say MPPT, they apparently aren't, so folks who use them will see no improvement. Second, you'd need both ammeter and voltmeter, in the live circuit, to see the real difference. And then of course every MPPT maker has their own proprietary charging scheme, unless they've just bought one of the new chips and done a "me, too!" of varying quality.


When I tested a BlueSky controller some years ago, I was expecting to see a conventional three-stage charging profile. Uhuh. The controller uses a microprocessor and a look-up table along with user programming. IF you have read the instructions and IF you have programmed the battery specs correctly, the controller *constantly* is supplying a slightly higher voltage than the batteries are at, at maximum amperage. So you may literally see 12.2v output from the controller to the batteries, when you are expecting 14.4 on the bulk charge. Once the battery gets charged a little higher, the controller steps up the voltage, maybe to 12.4, then 12.5, then 12.6, until it does go to full bulk charging voltage. But if you just stick a voltmeter in once, all you will see is that first low incremental voltage, with no idea of why it is "too low".


All of the reviews, all of the techs, all of the sources that have actually explored real MPPTs and tested them, agree that they will give you some 10-20% more power during the course of the day. The only things they disagree on are the exact amount of the boost (it varies) and the exact loss of the controller (typically 2-4%, still leaving a 10-20% net gain).


Whether they are worth the price for a possible 15% net gain? Depends on your situation and your options. But saying they don't work and work better, is like repeating that the bumblebee can't fly because it doesn't have the right lift-to-drag ratio. It just proves you haven't measured all the real factors.


12V panels may be producing 17-22V at peak output. 12V batteries can't use that voltage, so basically all the power produced by the high voltage is dumped and wasted by PWM controllers. Dumped. Versus an MPPT controller, which uses all of the extra voltage, converting it to extra amperage which will be used instead of wasted.
I'm curious of your response to:

Quote:
The MPPT regulator presents a relatively new and complicated technology which opens up fascinating opportunities. The basic idea is to generate from any random input voltage a defined output voltage with the assistance of the DC/DC converter. If a small voltage is transformed to higher voltages, we talk about a step-up converter. In contrast, there are also step-down converters. As a rule, MPPT regulators can only transform in one direction to still realize an acceptable degree of efficiency. Basically, step-down converters have a higher efficiency than step-up converters. DC/DC converters are high-frequency converters which emit correspondingly strong EMC radiated noise and should not be operated in the vicinity of radio equipment. What exactly is the advantage of such MPPT regulators versus a "normal" regulator? Twelve volt solar modules are designed in terms of the cell number such that ideal charge voltages will result for 12V systems with customary operating temperatures (25C air, 50C cell). The MPPT regulator here cannot realize any performance advantage. However, if the modules are operated during the winter season at low temperatures (-10C air, 20C cell), the solar module will generate considerably higher voltage than in the summertime. From this higher voltage, a slightly higher charge current can then be generated with the DC/DC converter. MPPT regulators can bring to bear their potential when modules are used which are not designed for 12V systems (house roof modules with 56 cells). For a 12V system, these modules always have an excessively high voltage so that the MPPT regulator can transform this excess voltage to additional charge current. If you shortlist an MPPT regulator, keep an eye on a high degree of efficiency over the entire current range. For example: If the MPPT regulator is rated for 10A and a 5A module is connected, you will now operate the regulator always in a power range from 0 to 50%. With overcast skies, your module supplies 0.5A to 1.0A; i.e. the MPPT regulator must here realize, at 5% to 10% of nominal power, a proper degree of efficiency of more than 90%. In any event, ask for a precise efficiency curve for the regulator. If the MPPT regulator has an efficiency of 90%, it means at the same time that permanently 10% of the module power are lost. The converter must first of all make up this permanent loss through voltage transformation before there will be any profit at all. Sales documentations of MPPT regulators frequently indicate fantastic performance gains of +30% or even +40%. For 12V modules, such performance gains are possible only at the North Pole. So the question remains: Why not use directly a module which is suitable for the application and doing without any elaborate and expensive technology after all, your system is supposed to work trouble-free for many years.
source:
https://www.sunware.de/sunware/techn...ge%20regulator
__________________

__________________
DotDun is online now   Reply With Quote
Reply

Tags
battery, lifepo4, LiFePO4 Batteries, sailing

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
LiFePO4 Batteries - Okay Tear Me Apart ;-) jallum Electrical: Batteries, Generators & Solar 395 03-12-2015 13:19
Voltage drop under load, amps read 99% ?? VVD Electrical: Batteries, Generators & Solar 25 28-06-2011 16:25


Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 10:52.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.