Trojon L16RE-B batteries

WD-40
WD-40 Registered Users Posts: 15
What do we think about using 8 of these on a 48 volt setup? I have used HD truck 8D's for many years. I Get about 3 years out of them. I have never tried to calc out my usage and my setup is not planned but pieced together like the other off grid folks here in the forest.
From my other post you know im trying to upgrade my setup.

I keep my batteries outside out of the weather. The temperature can get down to 0 degrees in the winter but the average low is 20 degrees. Summer never gets above 90. Is the cold a prob? I could put them in the basement but was worried about hydrogen buildup.

1600 watt pv
outback cc's
I use the x-5548 inverter for charging

plenty of generator options for charging from 25kw to two 7kw diesel gens.

Thank you again!

William

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Trojon L16RE-B batteries

    William,

    I am a big believer in sizing your system to your loads (including not using too large of gensets--many off-grid applications can run very nicely on 1,500-4kW gensets for battery charging--and be a lot more fuel efficient).

    Regarding using large 4v or 2v cells so you can build on series string (or a maximum of 2-3 series / parallel strings)--I am all for that! :D

    Battery capacity falls as temperature goes below freezing. Fully charged batteries will probably never freeze in your environment. However, if they get well discharged, they could run the risk the of freezing.

    With heat, if you can keep the battery average temperature below 80F--you will have better battery life.

    If they are outside, can you build a "root cell" type thing for them... Keep them between 32F and 80F and everyone should be much happier.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • WD-40
    WD-40 Registered Users Posts: 15
    Re: Trojon L16RE-B batteries

    Bill,
    The trojon L16RE-B batteries are 6 volt. I use the 25kw for welding and backup. I have two 7000 watt diesel generators and one of them is for backup. I use the 7kw for things like running the washing machine, blow dryer and other power hungry things. It only uses .32 gph at half load on spec but i am getting about .25 gph with my average use. Not to bad! The 25kw propane is wired directly to the x-5548 via x-remote start for low battery start up on AC2 and one of the 7kw diesel gens are on AC1 with manual wireless remote start. The propane is stored in two 500 gallon tanks away from the house and is only used for fridges, water heating and low battery generator start up. Propane storage is pretty safe. I also have 500 gallon of diesel here and it is safe to store unlike GAS! It is very hard to find diesel generators of less than 5kw

    thanks again,
    WD
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Trojon L16RE-B batteries

    The Trojans are excellent batteries.
    But you don't have enough panel to charge them. The 'B' series are, I think, 390 Amp/hrs and really do need at least 10% of that for charging to avoid sulphation and keep the electrolyte mixed. These 'tall case' batteries are particularly susceptible to stratification. And remember that charge rate is what is going in to the battery minus what is being drawn out at the same time (loads).
    I think you'd need to about double your array size to keep these batteries "happy":

    39 Amps * 58 Volts = 2262 Watts @ 80% = 2827.5 W array (not including load compensation).

    I could have done the calc wrong. Not sure about the charge V for a 48 Volt system for one thing. :blush:
  • dmiller
    dmiller Solar Expert Posts: 68 ✭✭✭✭
    Re: Trojon L16RE-B batteries

    Just buy enough batteries that you won't need to run the generator more than once a day. Since you have the generators you don't need more solar than you can fit or comfortably afford.

    Design your system around load. You have more than enough generator to mix during bulk and fully equalize. Just be sure you generator battery charger is a big enough quality unit with a temp sensor.
  • mikeo
    mikeo Solar Expert Posts: 386 ✭✭✭
    Re: Trojon L16RE-B batteries
    I keep my batteries outside out of the weather. The temperature can get down to 0 degrees in the winter but the average low is 20 degrees. Summer never gets above 90. Is the cold a prob? I could put them in the basement but was worried about hydrogen buildup.

    Those L16's have enough mass that if you put them in an insulated box, which is a good idea anyway for safety and keeping them clean, they will pretty much maintain the daily average temperature with only a few degrees swing. I would recommend at least 40 amps worth of panels if you are using them daily, that is about 10% of the 20 hour rate. If they are just for backup, 20 amps of panels should suffice.