6 VOLT BATTERIES, MINIMUM VOLTAGE

From my research AGM batteries can go to 11V But FLA batteries should never drop below 11.5V.

TBammer wrote:
What type of test is needed to check if the battery might have been abused in the past? Asking for friend.

I would start with a hydrometer.

Boon Docker wrote:

ktmrfs wrote:

Boon Docker wrote:
This info will help your friend.

TBammer wrote:
What type of test is needed to check if the battery might have been abused in the past? Asking for friend.

good info for 12V starting batteries and maybe marine/rv but not really valid for a GC2 battery. One, GC2 seldom if every have a CCA rating to use as a benchmark, Next They have a few very thick plates to much more internal resistance than a starting or marine battery. End result is if you try to load them to the typical load test, results in almost all cases will be "fail" even on brand new GC2. Unless the GC2 mfg gives a recomended load test current.

My experience is that loading a GC2 to between 1/2 and rated rated AH (60-100A on a typical GC2) gives some valid info,

I don't see anywhere that he mentioned a GC2.

nope he doesn't mention ANY info on battery type, so may as well give him info relevant enough to the two common battery types, 6V GC or 12V marine.

and the OP started the discussion stating he is using GC2 batteries.

ktmrfs wrote:

Boon Docker wrote:
This info will help your friend.

TBammer wrote:
What type of test is needed to check if the battery might have been abused in the past? Asking for friend.

good info for 12V starting batteries and maybe marine/rv but not really valid for a GC2 battery. One, GC2 seldom if every have a CCA rating to use as a benchmark, Next They have a few very thick plates to much more internal resistance than a starting or marine battery. End result is if you try to load them to the typical load test, results in almost all cases will be "fail" even on brand new GC2. Unless the GC2 mfg gives a recomended load test current.

My experience is that loading a GC2 to between 1/2 and rated rated AH (60-100A on a typical GC2) gives some valid info,

I don't see anywhere that he mentioned a GC2.

Boon Docker wrote:
This info will help your friend.

TBammer wrote:
What type of test is needed to check if the battery might have been abused in the past? Asking for friend.

good info for 12V starting batteries and maybe marine/rv but not really valid for a GC2 battery. One, GC2 seldom if every have a CCA rating to use as a benchmark, Next They have a few very thick plates to much more internal resistance than a starting or marine battery. End result is if you try to load them to the typical load test, results in almost all cases will be "fail" even on brand new GC2. Unless the GC2 mfg gives a recomended load test current.

My experience is that loading a GC2 to between 1/2 and rated rated AH (60-100A on a typical GC2) gives some valid info,

This info will help your friend.

TBammer wrote:
What type of test is needed to check if the battery might have been abused in the past? Asking for friend.

TBammer wrote:
What type of test is needed to check if the battery might have been abused in the past? Asking for friend.

My battery testing method I use at the start of each year is to use a GOOD charger to equalize the batteries making sure they are fully charged and each cell equalized. Note.... The typical WFCO charger commonly used in trailers will NOT fully charge, let alone equalize the battery. A Progressive dyanamics or Iota can.

Then for the specific battery, go to the mfg web site and see what they indicate for battery specific gravity (SG) and at what temperture.

Then with a calibrated hygrometer that has a temp compensation chart (not the cheapie at the local parts store) Friese (sp?) makes an excellent one. measure EACH cells SG and write it down. Then compare that to what the mfg says the NEW SG should be. If each cell is about the same reading and close to the spec'd SG, your good to go with a battery near tip top shape.

If one or more cells is much lower than the others try another equalizing charge, if it doesn't change, you've got weak cells and the battery is on it's way out.

if all cells are low, again your nearing battery end of life.

Note: I didn't mention doing a load test. On GC2 batteries load test is of very marginal use. GC2 are NOT designed for high loads like a starting battery so (1) if load testing a GC2 you don't want to use the common X times AH as the load, you'll be WAY over a valid test and (2) If the mfg does give a current load for a load test you can try it if you can find a adjustable load tester.

I've never tried to load test a 12V marine/rv/starting battery so I have no clue as to how valid a load test is on such a battery.

And as a check with the battery AH rating for 20 or 24hours, and if you have a load that would match that AH rating (AH/20) you could run a load on it and check resting voltage at 6hours and 12 hours to see how close you are to 75% and 50% SOC. If at 6 hours your below the 75% SOC, don't go a full 12 hours, go say 8 measure again, if not at 50% continue. in the end you should have an idea of battery AH capacity vs. rated and an idea of battery condition.

What type of test is needed to check if the battery might have been abused in the past? Asking for friend.

"Right now I'm testing how long they will run the furnace in anticipation of several days boondocking."

Experiment away but if you are not refilling your wet batteries daily their life will be shortened. 11.75 volts resting is about 30%...another battery life shortening event.

BarneyS wrote:
This might be helpful to somebody.
It was taken from The 12 volt side of life.

This should be printed on every deep cycle battery.