Car battery with possible dead cell

[Physics Hunter]

We have a car that, because we don't drive it around that much, we leave it on a trickle charger we got from Harbor Freight:

https://www.harborfreight.com/automa...ger-64284.html

We've kept it plugged into that charger for over a year when we're not driving it. Never had a problem. Recently, I had trouble turning it over. I checked the battery and it was showing 11v. I checked the trickle charger and our multi-meter reads 14v coming off of it.

As far as it being on the trickle charger that caused it to fail, there's another vehicle that we've had a trickle charger on it since 2018 and that battery has kept going. At this point, I'm thinking one of the cells in the battery in the other car has gone bad.

Yeah, natural for lead acid batteries to grow little stalactites of Lead from Anode to Cathode (or is it the other way? ), then that cell arcs out and the battery essentially loses 1.5V.

[Physics Hunter]

I have a lot of vehicles with batteries, over 20, and consider the Battery Tender (a trickle charger for motorcycles) a money saving miracle.
Over off season for whatever vehicle I rotate the 'Tender around to the vehicles that mostly sit, moving them (I own several) every 5-7 days, and now most batteries last 5-10 years.

[kazenatsu]

We've kept it plugged into that charger for over a year when we're not driving it.

I really do not know but I think you can't just plug a battery into a trickle for a whole year and expect it to be completely okay. Maybe every two months or so it needs a stronger full charge. Leaving it that long if it's not fully charged can lead to permanent damage, perhaps especially in colder weather.

[Northern Rivers]

I am not a mechanic but if the car won't start I'd tend to believe the 11.
But why not just run the car every few days like we sometimes do in the winter?

Yep. My big CUMMINS gensets need to be run through not more than once a week. Since I'm going away for about two months...I'm hoping my boys will keep on it.

Batteries vary on a production line, from one to the other. It's probably the case...

[tlmjl]

battery is weak...replace

trickle charging, otherwise known as a maintainer, is not the problem in this case. If the battery was good the maintainer would keep it at or above 13.5.

[ruthless terrier]

you can't just plug a battery into a trickle for a whole year and expect it to be completely okay. Maybe every two months or so it needs a stronger full charge. Leaving it that long if it's not fully charged can lead to permanent damage, perhaps especially in colder weather.

it's called sulfating. the lead gets coated with the sulfate and no longer holds a charge. not fixable.

[Dan40]

We have a car that, because we don't drive it around that much, we leave it on a trickle charger we got from Harbor Freight:

https://www.harborfreight.com/automa...ger-64284.html

We've kept it plugged into that charger for over a year when we're not driving it. Never had a problem. Recently, I had trouble turning it over. I checked the battery and it was showing 11v. I checked the trickle charger and our multi-meter reads 14v coming off of it.

As far as it being on the trickle charger that caused it to fail, there's another vehicle that we've had a trickle charger on it since 2018 and that battery has kept going. At this point, I'm thinking one of the cells in the battery in the other car has gone bad.

Cheap trickle chargers can kill a battery.

[crcook84]

Upon opening it up, it looks like a number of the cells needed topping off anyways. I've topped them off and we'll see in a few hours how well the charger brings the battery back to 12v. Furthermore, I was fortunate that Walmart had one more of these in stock:

https://www.walmart.com/ip/Mainstays...ottle/14964974

Made it much easier to drip the distilled water into the battery. Furthermore, I can't help but wonder if providence played a part in one bottle being left on the shelf.

[Dan40]

Upon opening it up, it looks like a number of the cells needed topping off anyways. I've topped them off and we'll see in a few hours how well the charger brings the battery back to 12v. Furthermore, I was fortunate that Walmart had one more of these in stock:

https://www.walmart.com/ip/Mainstays...ottle/14964974

Made it much easier to drip the distilled water into the battery. Furthermore, I can't help but wonder if providence played a part in one bottle being left on the shelf.

Here is a shock for you. If you suspect a certain cell is bad, dip your little finger in the cell. Just get a tiny bit on your finger. Taste it. If the cell is good the acid taste will let you know immediately. If the cell is bad the liquid will taste like water. Not good water, but not acid. OR put a load on the battery (BLOW IT CLEAR OF ANY AIR AROUND IT,,, HYDROGEN) then look in each cell. The one bubbling under load is bad

[crcook84]

I found a video on YouTube in which someone was using a clamp meter to see what type of amperage was going through their battery. He said that a sulfated battery will read .1 amps on the clamp meter if there is sufficient sulfate on the cells. My clamp reading was 4.4 amps. So, at this point, things seem to indicate that the cells have not sulfated.


Edit: I, finally, found the date of manufacturing on the battery. It was stamped into the plastic. So, it was hard to see. The date is 2016. That means it's between 6-7 years old.