wopachop

Who run bartertown

Senior Member

Joined: 11/17/2006

View Profile

Offline
|
Wanted to share this attempt at getting a little more use out of this battery. We accidentally drained it all the way down to 0.000v. Ive never seen my charger display that before. Even using Pb mode and calling it a 1 cell battery it still would not begin the charge process.
The battery tender charger as well didnt want to begin the charge. We got jumper cables and jumped the battery for a few seconds and then the battery tender kicked in. Its the 5a version of battery tender brand.
I had 2 questions that the smart fellas here might be able to shed some light on. Im assuming the battery is dead, because one of the kids left the 12v LED lights on. I had an adjustable voltage regulator hooked up to (2) of the 8v batteries and the regulator knocks it down to 12v.
What i found strange is the battery with the positive lead was low, while the battery with the negative lead was completely dead to 0.0v.
1. Why did the negative battery die, instead of both batteries dying? The battery that died was 1 year old. While the battery that lived has got to be over 10 years old.
2. Second question is when i hook up my fancy charger to some of the batteries, the voltage will flash, then disappear. Its like it loses and regains connection. Sometimes if i catch it at the right time i can get the charge to start. But usually it tells me "connection error." What is going on inside to batteries to make the connection come and go like that? Pretending my alligator clips and nice and tight on clean metal. Only some of the batteries acted this way. My fancy charger didnt like those batteries. But the 5a battery tender has no problem recognizing them and charging away.
![[image]](https://i.imgur.com/NJ654snl.jpg)
|
wopachop

Who run bartertown

Senior Member

Joined: 11/17/2006

View Profile

Offline
|
3rd question i forgot was about resistance. What can we learn from those numbers? I forgot to write it down darn it. I probed the battery with 0.0v and i think it said something ilke 2.47.
Then probed a good battery and i think it read 0 ohms. My bad not writing it down. Was a few days ago.
|
2oldman

south

Senior Member

Joined: 04/15/2001

View Profile

Online
|
Why do you have 8v batteries?
|
wopachop

Who run bartertown

Senior Member

Joined: 11/17/2006

View Profile

Offline
|
Brings up a good 4th question.
4. Does the size of the cell effect its ability to be revived? My first thought is a 3s battery in normal RV size would have a better chance than a 6s.
|
Lwiddis

near Bishop, California

Senior Member

Joined: 08/12/2016

View Profile


Good Sam RV Club Member
Online
|
I’m a non-believer in RV battery revival. Hocus pocus, alakazame!
Winnebago 2101DS TT & 2020 Chevy Silverado 1500 LTZ Z71, 300 watt solar-parallel & MPPT, Trojan T-125s. TALL flag pole. Prefer USFS, COE, BLM, NPS, TVA, state & county camps. Bicyclist! 14 year Army vet-11B40 then 11A - (MOS 1542 & 1560) IOBC & IOAC grad
|
|
time2roll

Southern California

Senior Member

Joined: 03/21/2005

View Profile


Good Sam RV Club Member
|
None of this matters until you install a 12v battery (or 2x 6v).
Or is this a 36v or 48v golf cart? Or something else?
2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
675w Solar pictures back up
|
wopachop

Who run bartertown

Senior Member

Joined: 11/17/2006

View Profile

Offline
|
2oldman wrote: Why do you have
time2roll wrote: None of this matters
Not off to the best start.
|
time2roll

Southern California

Senior Member

Joined: 03/21/2005

View Profile


Good Sam RV Club Member
|
I am not sure what we are working with. The bottom of the second picture says 24.755 volts.
Yes some chargers need to see voltage within specification before they will start charging. They all have different specs.
|
CA Traveler

The Western States

Senior Member

Joined: 01/03/2004

View Profile

Offline
|
Batteries can have strange/unexpected results. Plus you have mismatched batteries physically and 9 years difference so failures should be expected not questioned.
Find a good battery shop and have them load tested especially since discharged batteries are not happy.
From an RV standpoint replace them. As an experiment see what you can learn.
2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland
Bob
|
wopachop

Who run bartertown

Senior Member

Joined: 11/17/2006

View Profile

Offline
|
time2roll wrote: The bottom of the second picture says 24.755 volts.
Good eyes!! I went with dual 12v power supplies. Looking back it was probably a waste of money. Also its rare but if one power supplies fails while in use it can damage the charger. But with a single power supply if it fails there is less chance of damage.
|
|