Tracking an aging battery

[Snagglefoot]

Here is an almost four year old Walmart Everstart, made in the USA, with serviceable caps. I’ve kept up with water additions and it still starts the Ford 3.0 just fine but is starting to show its age based on the battery voltage and CCA reading. I’ve posted photos of the voltage and CCA reading after fully charging it and the same the same readings after letting it sit for a week outside in the car with the usual voltage drain for the clock. I plan to see how it does with limited use, parked in freezing conditions and the usual clock voltage drain. A little science project for the next two months.

 

[JHZR2]

These values are contingent upon temperature. Are you keeping temperatures constant? Have you evaluated what the parasitic draw is from the car?

Will be interesting to watch!

 

[Snagglefoot]

These values are contingent upon temperature. Are you keeping temperatures constant? Have you evaluated what the parasitic draw is from the car?

Will be interesting to watch!

I’ve found the difference with this battery between 32 F and 68 F was not much but I will check when the temps get lower. We may go to -25 F this winter. Good idea on the parasitic loss. I will measure that.

 

[Kira]

This admittedly simple scale for measuring battery health was based on readings 4-12 hours after shut down.
I'd assume a week idle wouldn't be that different.
12.8v = New battery
12.5v = 3 year old battery
12.3v = start battery shopping
12.2v = Failed battery

1) Will the first REALLY COLD day kill Snag's battery?
2) Might it last to the first REALLY HOT day?

Q: Do you wrap an ampmeter's leads around the battery's positive cable then crank the vehicle to get a CCA reading?

 

[JHZR2]

This admittedly simple scale for measuring battery health was based on readings 4-12 hours after shut down.
I'd assume a week idle wouldn't be that different.
12.8v = New battery
12.5v = 3 year old battery
12.3v = start battery shopping
12.2v = Failed battery

1) Will the first REALLY COLD day kill Snag's battery?
2) Might it last to the first REALLY HOT day?

Q: Do you wrap an ampmeter's leads around the battery's positive cable then crank the vehicle to get a CCA reading?

Thing is that the electrochemical potential should not change in a manner of which you propose.

Some of the surface charge behaviors we typically see? Sure, because the surface area and characteristics of the plates are changing.

But open circuit (unloaded) voltage versus SOC should not. As the amount of accessible energy decreases, the observed voltage will decrease because the SOC is dropping faster. The tank is getting smaller.

 

[Snagglefoot]

This admittedly simple scale for measuring battery health was based on readings 4-12 hours after shut down.
I'd assume a week idle wouldn't be that different.
12.8v = New battery
12.5v = 3 year old battery
12.3v = start battery shopping
12.2v = Failed battery

1) Will the first REALLY COLD day kill Snag's battery?
2) Might it last to the first REALLY HOT day?

Q: Do you wrap an ampmeter's leads around the battery's positive cable then crank the vehicle to get a CCA reading?

I like that. Let me add this randomly found sheet and suggest these mods.

12.8v = New battery with fresh top charge.
12.7 v = 100%
12.5 v = 80% ( 2 years old depending where you live.)
12.4 v = 75% ( 3 years old depending where you live)
12.2 v = 50 % Start shopping.
12.0 v = 25%. No more winters for you.

I used the clips on the Schumacher BT-174 and tried to get a good hold on the terminals.

 

[Snagglefoot]

These values are contingent upon temperature. Are you keeping temperatures constant? Have you evaluated what the parasitic draw is from the car?

Will be interesting to watch!

Yes, so here is an update. I did check it for parasitic loses. It was a bit of a saga. With the lights off and key off, I took off the negative battery cable and, setting my multimeter to 10 A DC, I put the probes on the cable and the negative terminal. I was surprised to see 4.5 Amps. I then realized I had the driver's side door open and because I had the hood open, I did not realize the ceiling light was on, so when I finally saw that, I closed the door. Also, it takes 20 seconds for the light to go out, so you have to be patient with the test. Now, the drain was 2.2 Amps. Holy cow that's a lot. I checked the net and there were plenty of folks who saw drains on fuse 33. I checked mine and sure enough I was able to get the drain down to 100 mA or so by pulling fuse # 33 which controlled the ICP, gage cluster, hazard flasher, windows, and interior lighting. The owners manual did not actually say windows and interior lighting were on this 15 Amp fuse, but they were.

This car is a 2005 Taurus. I did some research and the advice was to pull the ICP, Integrated Control Panel, which on a Taurus is the radio and HVAC control in on panel and unplug the power to each segment. I did that, put the fuse back in but no, there was no reduction in the draw.

I then checked the Ford Taurus forum and a guy named Jeff K, (I'm assuming its not our resident Tesla Fan , Jeff K on Bittog.) Anyway he cleared it up that you should use clamps to install your multimeter on the negative battery cable and the negative terminal, put the fuse back in, and then wait 40 minutes to let the modules go into the "sleep" mode. I have seen some references to this but I thought you could just spot check this. Nope, you need to be connected in with the multimeter and then let it go into the sleep mode. The end of the story is that the 2.2 Amps went down to 34 mA in 40 minutes. It turned out there was no significant loss. Here are some shots of how I used a battery charging clamp (not turned on) to grab the terminal so I had something to hang on to with the small clip from the multimeter. The other clip is connected to the negative battery cable.

 

[Snagglefoot]

So I checked after a 50 mile round trip and have 12.36 V and 838 CCA with an indicator light saying that it’s weak and needs a charge. I’m going to top it up to get it ready for some colder weather coming.

 

[Snagglefoot]

Charged it up. Fresh off the charger it is 12.96 V and 802 CCA. Interesting how the CCA reading can actually be smaller. Perhaps it’s just an accuracy issue on this inexpensive battery test. Anyway, the temps will be dropping to the 5 F range later this week.

 

[wrcsixeight]

The CCA is calculated by impedence.
The tester puts a load on the battery and sees how much the voltage drops and does some math.

You can exert more or less pressure on the clamps at the battery terminals, and manipulate the CCA reading.

If your battery has removable caps:
https://www.amazon.com/OTC-4619-Professional-Battery-Hydrometer/dp/B0050SFVHO

Make sure no bubbles stick to the float.
Give it time for the electrolyte's temperature to change the silicon portion housing the thermometer, which tells one how much to add or subtract from the reading on the float.
You will likely find that when your charger quits, saying the battery is full, that the specific gravity reads well below 1.265, and flooded batteries, intended for northern climates, might have specific gravity, when fully charged, in the 1.300 range.
If the electrolyte pulled into the hydrometer while charging, is cloudy and grey, that is a sign the battery is nearing end of life

Often leaving the lights on to drag battery voltage below 12.6v or so, then restarting the charger, over and over, can allow one to incrementally raise the specific gravity up towards the 1.265+ region indicating the battery is charged near its full potential remaining capacity.

I was highly reluctant to get and use a hydrometer.
I regret my reluctance, as it equated to voluntary ignorance and premature battery failure, as I intentionally deeply cycle my batteries.

Furious that my plug in smart charger could not get my cycling battery upto 1.265+, I got an adjustable voltage power supply, in order to hold the battery at high voltage until specific gravity maxed out, and every battery I have owned since, has had an impressive lifespan.

 

[Snagglefoot]

Did a start at 25 F to move it into the garage for some maintenance. No issues but only 12.1 V prior to the start. Getting colder later this week.

 

[Snagglefoot]

Did a start at 11 F. Just a bit worse than 25 F. The spin was just a bit slower. Voltage is still hanging in above 12 V. Measured CCA is 708 A.

 

[Donald]

Here is an almost four year old Walmart Everstart, made in the USA, with serviceable caps. I’ve kept up with water additions and it still starts the Ford 3.0 just fine but is starting to show its age based on the battery voltage and CCA reading. I’ve posted photos of the voltage and CCA reading after fully charging it and the same the same readings after letting it sit for a week outside in the car with the usual voltage drain for the clock. I plan to see how it does with limited use, parked in freezing conditions and the usual clock voltage drain. A little science project for the next two months.

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Who made that battery? No "EP" in the serial and the caps are not JCI.

 

[Snagglefoot]

Who made that battery? No "EP" in the serial and the caps are not JCI.

It only says made in the USA, and has removable caps. I’m wondering myself.

 

[Snagglefoot]

Anyway, that’s the coldest of the weather for January. The forecast to the end of the month indicates it’s warming. I’ll see if we get any colder weather in February to put this battery to the test.

 

[Snagglefoot]

Well, the temperature got down to - 5 deg F. With the car outside for the past week while the temperature dropped I finally got a voltage reading of under 12 V and a measured CCA of 650 A. And YES, it started. It really wasn't that bad of that of a start. Of course, if the temperature was back up at 68 deg F the voltage would have been higher than 12. Looks like this battery is probably good for some time yet. The oil in the engine was Pennzoil Platinum 5w20. Readings were done with the electronics in a undisturbed mode I.e. car door was not opened prior to taking the readings.

 

[IcarusLSC]

AC conductance testers are notoriously quite inconsistent among testers. Best to use same tester each time which you are. They are ok for cranking tests but really don't tell us anything about the capacity or state of health of a battery (which is arguably just as important if you want to leave your car for a few days and have it start!) I'd pick a carbon pile tester over most any no-name conductance tester if you want to know SoH imho...

Some interesting reading here about SoH and capacity vs cranking testing:
https://marinehowto.com/are-battery-conductance-testers-worth-it/

 

[Snagglefoot]

I agree with that assessment. However, the tester did identify the battery as “ weak” and directionally, the CCA went down with temperature. It is suspicious that the CCA measured at -5 F was still 650, because the factory CCA is also 650. However, it did do a start.

I’m thinking the tester is too optimistic but yet indicates a “weak” battery. Probably good enough for the $50 bucks it cost.

 

[Snagglefoot]

Well, spring is here. The battery was at 12.2 V at 45 F this morning after sitting all week. This is still a good battery after four years of regular starts including plenty of sub zero starts. Walmart Everstart. No plan to replace it just yet.

 

[Snagglefoot]

We’re back. The battery was at 12.1 V at 50 F this morning after sitting through the long weekend. I’ll see how it does as it gets colder this fall. Notice I’m getting the same yellow “weak” indicator light as last winter. I have fresh 5w30 in the crankcase. If it goes below 12 V much, I’ll probably get a new one.