Sunsaver MPPT configuration for StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium

CraigC
CraigC Registered Users Posts: 16
I ordered my StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium (SP-12V100-EP) battery and am awaiting it's delivery. In the meantime I'd like to get my Morningstar Sunsaver MPPT programmed to cooperate with it. The published specifications for the SP-12V100-EP are below. As you can see it has an internal BMS so I'm not concerned with cell balancing. I'd like to discuss the custom setting of the Sunsaver MPPT so that keeps the battery at an optimum charge level but doesn't receive a non-stop current. I'm new to the solar battery charging field but after tinkering with the Sunsaver MPPT with a lead acid battery and the absence of any other info on how to get these two devices to coexist I'm currently planning on the following Sunsaver settings:

Sunsaver MPPT settings
Absorption voltage - 14.4V
Float Voltage - 14.1V
Float Low battery threshold - 3V (battery low voltage disconnect is 8.2 so this will never be reached)
Float Cancel threshold - 3V (same as above)
Time before float - 5 minutes
Time before float low battery - 5 minutes
Time until float exit - 5 minutes

Temperature compensation - 0
Battery high voltage disconnect - 14.5V
Battery high voltage reconnect - 14.1V
Max Regulation voltage limit - ?????


StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium (SP-12V100-EP) battery info
Voltage: 12V
Capacity: 100Ah, 1280Wh
Chemistry: LiFePO
Weight: 32.6lbs (14.8kg)
Dimensions: 13"(L) x 6.8"(W) x 9"(H), [330mm(L) x 172mm(W) x228mm(H)]
Life Cycles: 2,000 @ 80% DOD
BMS: YES (Internal)
Max Charge Voltage: 14.6V
Discharge Cut-off Voltage: 8.2V
Max Charge Current: 50A
Max Discharge Current: 100A
Max Starter Current: 300A
Operating Temperature: -22°F to +140°F, (-30°C to +60°C)


For those of you who can tell that I really don't know what I'm doing please feel free to contribute. Please don't tell me to buy a different battery or controller, my objective is to optimize what I have.

Thanks in advance......

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Sunsaver MPPT configuration for StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium

    I have moved this to the advanced section because frankly you're trying to use two items that are basically incompatible. If anyone wants to offer some advice on how to get them to work together without fires or explosions, feel free.
  • CraigC
    CraigC Registered Users Posts: 16
    Re: Sunsaver MPPT configuration for StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium

    I'm sure you can tell I'm new to this,please tell me what makes them incompatible. thanks
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Sunsaver MPPT configuration for StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium
    CraigC wrote: »
    I'm sure you can tell I'm new to this,please tell me what makes them incompatible. thanks

    Mostly the limitation of the SunSaver's charging specs which are only adjustable up to a point. The LiFePO battery may require quite a different charging profile from what the SunSaver can provide.

    If the battery isn't charged properly it will probably die sooner rather than later. How much of a problem would that be for you? For instance the SS will go only to 14.4 Volts, so what effect will that have on the battery whose maximum is 14.6? Perhaps none noticeable, perhaps that extra 0.2 Volts is critical. And then there is the time spent at that Voltage.

    Current: Morningstar's output is 15 Amps max. The battery spec says 50 Amps max. Will it charge at 15 Amps? It should, but how well and how long will it take?

    That it has a built-in BMS is good, providing you can pull enough current and Voltage from the SS to work it properly. Again the issue of Voltage and time. If there's enough panel on the SS to keep it's output up for most of the day that will help.

    If this were a standard 100 Amp hour 12 Volt lead acid battery it would be no worries. I am not familiar with the charging characteristics of this battery type but some of the guys here do have experience with LiFePO batteries and hopefully they will chime in with some insight as to how effective this combination will be.
  • CraigC
    CraigC Registered Users Posts: 16
    Re: Sunsaver MPPT configuration for StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium

    I'm trying to get the Sunsaver to mimic the charger they sell (specs from their website below). I guess I should set high voltage to 14.6V or a hair below and set the time before float as short as possible so it doesn't sit in the absorption phase.

    Charger specs from website

    These chargers are constant current, constant voltage (CCCV) "Smart" chargers for 12V LiFePO or lead acid batteries. "Smart" chargers stop charging once 14.6V is reached.

    Max Charge Voltage: 14.6V
    Max Charge Current: 5-6A
    AC Input: 110V-240V 50/60Hz 50VA
    Dimensions: 5.9""(L) x 3.5"(W) x 2"(H), [150mm(L) x 90mm(W) x 50mm(H)]
    Weight: 1.4lbs, [589g ]

    LED 1: Red Power On
    LED 2: Red Charging
    LED 2: Green Charged

    Can be left on StarkPower battery and will restart with low voltage signal from battery. Fully isolated, to hookup multiple chargers to each 12V battery to balance multiple batteries in series with a max DC voltage of 48V.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Sunsaver MPPT configuration for StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium

    The IUIa charge profile is not unusual.
    Except in solar applications.

    So again it comes down to how the change in profile will affect battery life/performance. I don't even have a guess for that one. :blush:
  • CraigC
    CraigC Registered Users Posts: 16
    Re: Sunsaver MPPT configuration for StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium

    The thread Sunsaver MPPT & LiFePO4 Batterys http://forum.solar-electric.com/showthread.php?5173-Sunsaver-MPPT-amp-LiFePO4-Batterys seem like a more appropriate thread so I posted my response (below) there too. Unless there is some special interest for the SunSaver MPPT and the StarkPower battery I think this thread can be closed.

    Response I posted on the other thread:

    After a little research I decided to use a modified version of what the author of the blog http://solarbodge.blogspot.com/ was using. He has a 24V system and I have a 12V. Here's the settings I'm using to charge my StarkPower SP-12V100-EP 12V 100Ah LiFePO4 (http://store.starkpower.com/12V-100A...tery_p_24.html with my Panasonic HIT POWER 225A;

    Absorption Target Voltage: 14.00 (3.50)
    Absorption (Constant Voltage) Cumulative Time : 10 mins
    Absorption Time Extended: none
    Float Target Voltage: 13.4 (3.35)
    Float Exit Time: 720 minutes
    HVD (trigger): 14.50 (3.625)
    HVD (release): 13.20 (3.30)
    Max Regulation Voltage: 14.20 (3.55)
    Temperature Compensation: Pack -30mV/C (25C to 80C)

    Anyone have any recommendation or improvements?

    Thanks,

    Craig
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Sunsaver MPPT configuration for StarkPower Ultra Energy 12V 100Ah LiFePO4 Lithium

    OK, I will close this thread so the comments are directed to your current set of posts.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
This discussion has been closed.