Watering battery cells

Surfpath
Surfpath Solar Expert Posts: 463 ✭✭✭
Just a wee beginner-ish inquiry. I just topped off all the cells in my Trojan L16 bank. Here's a photo of the battery courtesy our host's site.

As I got to the 3 cells on the battery in the corner of my solar room it got a little harder for me to accurately get all the battery water in each cell. The cables, the wall behind the battery and distance I had to stretch all got in the way. A little spillage occurred on the top of the battery. Although not much water spilled out it seemed to quickly spread out thin on the smooth Trojan "polygon" case.

It made me wonder. If there was enough water to span the ~6 inch gap between my (+) and (-) L post terminals on that corner L16 battery, would this be a major issue?
Outback Flexpower 1 (FM80, VFX3048E-230v, Mate, FlexNetDC) 2,730watts of "Grid-type" PV, 370 AmpHrs Trojan RE-B's, Honda 2000 watt genny, 100% off grid.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Watering battery cells

    You need to check the three cell caps individually (3x 2 volt cells in series).

    If you have the 2 volt L16--You will need to double check... At least some of the first Trojan "2 volt" cells were actually three 2volt cells in parallel. So each cell needed to check SG/Water levels (the are separate cell cavities).

    Typically you fill the cells about 1/2 full--And avoid filing all the way--When the cells heat up and trap gas when charging, a near full cell will burp electrolyte out the top.

    Normally, you never add electrolyte--Just add distilled water in normal operation. If your batteries burp out too much electrolyte, you are losing the sulfuric acid itself--Not a good thing.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: Watering battery cells

    On my batteries, the terminal penetrations were sealed with some sort of black sealent, so that the water standing on top of the battery would not short them. Since this is the same manufacturer, your terminals may have a similar protection.
  • Surfpath
    Surfpath Solar Expert Posts: 463 ✭✭✭
    Re: Watering battery cells
    BB. wrote: »
    You need to check the three cell caps individually (3x 2 volt cells in series).

    If you have the 2 volt L16--You will need to double check... At least some of the first Trojan "2 volt" cells were actually three 2volt cells in parallel. So each cell needed to check SG/Water levels (the are separate cell cavities).

    Typically you fill the cells about 1/2 full--And avoid filing all the way--When the cells heat up and trap gas when charging, a near full cell will burp electrolyte out the top.

    Normally, you never add electrolyte--Just add distilled water in normal operation. If your batteries burp out too much electrolyte, you are losing the sulfuric acid itself--Not a good thing.

    -Bill

    Thanks for the responses. To clarify. I am adding distilled water to the 3 caps on each 6v battery to the manufacturers recommendations.

    The issue is as follows: do I need to be extra careful about water accidentally spilling on top a battery when filling hard to get cells.

    Unlike North's terminals my version goes just about flush (1mm?) to the battery case, as sort of seen in this photo here. There is no protective material.
    Outback Flexpower 1 (FM80, VFX3048E-230v, Mate, FlexNetDC) 2,730watts of "Grid-type" PV, 370 AmpHrs Trojan RE-B's, Honda 2000 watt genny, 100% off grid.
  • n4wff
    n4wff Solar Expert Posts: 48 ✭✭
    Re: Watering battery cells

    Are you talking about water and electricity possibly shorting out? I wash my 48v bank regularly with a garden hose, and it has never been a problem.
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: Watering battery cells

    Surf..

    You do not need to be too worried about spilled Distilled Water on the tops of the batteries.

    Many of us wash the battery tops (and sides, too if necessary). Just use a dish or other towel to soak up the water. It is a good idea to use a dilute solution of Baking Soda in water to clean the battery tops, and many use clean water to remove (most) of the soda when done with cleaning.

    If you can lay out the battery bank to allow the easiest possible maintenance, you and perhaps the batteries will be happier.

    Good Luck, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Surfpath
    Surfpath Solar Expert Posts: 463 ✭✭✭
    Re: Watering battery cells
    n4wff wrote: »
    Are you talking about water and electricity possibly shorting out? I wash my 48v bank regularly with a garden hose, and it has never been a problem.

    That's it exactly. Glad to hear it's not an issue.
    Outback Flexpower 1 (FM80, VFX3048E-230v, Mate, FlexNetDC) 2,730watts of "Grid-type" PV, 370 AmpHrs Trojan RE-B's, Honda 2000 watt genny, 100% off grid.
  • H2SO4_guy
    H2SO4_guy Solar Expert Posts: 213 ✭✭✭
    Re: Watering battery cells

    I dump water or water w/ baking soda on top of batteries w/ a 2 liter pop bottle every 3 months or so and never a problem. I don't want to leave any soda on top so it can't get into the cells when the caps are open so I rinse well. I do wipe them down with paper towels afterwards because if you use a cotton towel, it won't last too long after that project!

    Skip
    12K asst panels charging through Midnite Classic 150's, powering Exeltechs and Outback VFX-3648 inverter at 12 and 48 volts.  2080 AH @ 48 VDC of Panasonic Stationary batteries (2 strings of 1040 AH each) purchased for slightly over scrap, installed August 2013.  Outback PSX-240X for 220 volt duties.  No genny usage since 2014. 
  • ramloui
    ramloui Solar Expert Posts: 109 ✭✭
    Re: Watering battery cells

    Pure water, as in distilled and demineralized, does not conduct electricity. It is the soluble stuff that dissociates in anions and cations that make water conductive.
    Off-grid cabin in northern Quebec: 6 x 250 W Conergy panels, FM80, 4 x 6V CR430 in series (24V nominal), Magnum MS4024-PAE