12v batteries -need help on choosing them

edd_h
edd_h Registered Users Posts: 8
Hi
Ive recently been looking at a solar panel system, and am now looking at the batteries to buy for the system, and have found the following - they seem really cheap and good quality, can they be used / are they effective?

VARTA

SILVER dynamic

type I1

BATTERY

610 402 092


12V 110Ah 920A(en)




are they any good?
at the eqiverlant of 75 dollars a battery.
I've just found 10 on ebay uk for 380 sterling = 600dollars - really cheap!

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,422 admin
    Re: 12v batteries -need help on choosing them

    According to this website, the are listed as a car battery.

    From the sales brochure (large PDF download), I don't see anything that says they are designed for deep cycle application (is an AGM type battery).

    Automotive batteries are typically designed for shallow discharge (15% or so discharge) and high current for starting and would not have very good life if use in a deep cycle application (solar power).

    If your application only needed "small amounts" of power (15% discharge), but in larger surges, this battery may work for you.

    My 2 cents, I do not know anything else about this battery line.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • hillbilly
    hillbilly Solar Expert Posts: 334 ✭✭
    Re: 12v batteries -need help on choosing them

    If this is in relation to the system that you've been proposing in other threads I'd say that you'll have an issue here of insufficient capacity (particularly if they are automotive batteries). Be aware that it's generally not advisable to parallel too many batteries, as you'll have issues with uneven charging and discharging. Usually most folks try to use only 1 or 2 parallel "sets" of batteries, for 12V system examples: 2 6V batteries in series, 4 6V batteries in series/parallel (two sets of two), 2 12V batteries in parallel, etc... Any more than 3 parallel sets and you're likely to have some problems, buying 10 of them would not be a good idea unless you were operating a 120V system (1 series string) or something.
  • GreenPowerManiac
    GreenPowerManiac Solar Expert Posts: 453 ✭✭✭
    Re: 12v batteries -need help on choosing them

    Better off scrapping the car battery idea and investing in something that at least says "Deep Cycle" on it. Amp hours can be within 10-15% of each other without charging problems, however, nothing beats the same hours. Gels are good batteries too if you can find them cheap enough.

    How much power (wattage) do you wish to invest in Solar ?
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 12v batteries -need help on choosing them

    my comments in bold.
    Better off scrapping the car battery idea and investing in something that at least says "Deep Cycle" on it.

    agreed.

    Amp hours can be within 10-15% of each other without charging problems,

    i disagree with that statement as you should have the same battery make and model and near the same age and condition. you will have problems being off tolerance by 10-15%.

    however, nothing beats the same hours.

    exactly, so buy the same new batteries. even new batteries of different makes with the same ah rating could charge/discharge differently enough to cause problems with each other.

    Gels are good batteries too if you can find them cheap enough.

    gels may be slightly cheaper as they aren't as good as other types in their charge/discharge characteristics. they are a sealed battery, though, making them nonspillable and maintenance free.


    How much power (wattage) do you wish to invest in Solar ?