Reply
 
Thread Tools Search this Thread
 
Old 17 March 2008, 13:36   #1
Member
 
richardjawilson's Avatar
 
Country: UK - England
Town: London, boat Dartmouth
Boat name: Lark
Make: Capelli Cap 32 WA
Length: 10m +
Engine: Yamaha 250x2
MMSI: 235096621
Join Date: Feb 2006
Posts: 189
Battery voltage.....

Good afternoon all. I am checking my batteries and 1 of the pair is not holding charge that well. Would anyone know what my voltmeter should read on a battery that has been fully charged.

One is showing just over 13 volts after 24 hours charging whilst the other is only showing 11.04.


Thanks richard.
__________________

__________________
richardjawilson is offline   Reply With Quote
Old 17 March 2008, 14:04   #2
Member
 
Country: Other
Town: San Carlos, Mexico
Boat name: INDE
Make: LOMAC 730
Length: 7m +
Engine: 200 Merc.
MMSI: Please press 1
Join Date: May 2006
Posts: 1,688
Send a message via Skype™ to Limey Linda
Quote:
Originally Posted by richardjawilson View Post
Good afternoon all. I am checking my batteries and 1 of the pair is not holding charge that well. Would anyone know what my voltmeter should read on a battery that has been fully charged.

One is showing just over 13 volts after 24 hours charging whilst the other is only showing 11.04.


Thanks richard.
Looks like you have a duff battery. A good one should measure 12.5-12.8with no load. The fact that there is a difference is significant. Sorry, buy a new one.
__________________

__________________
Running around like a head with it's chicken cut off.
Limey Linda is offline   Reply With Quote
Old 17 March 2008, 14:07   #3
Member
 
Country: Other
Town: San Carlos, Mexico
Boat name: INDE
Make: LOMAC 730
Length: 7m +
Engine: 200 Merc.
MMSI: Please press 1
Join Date: May 2006
Posts: 1,688
Send a message via Skype™ to Limey Linda
Quote:
Originally Posted by richardjawilson View Post
Good afternoon all. I am checking my batteries and 1 of the pair is not holding charge that well. Would anyone know what my voltmeter should read on a battery that has been fully charged.

One is showing just over 13 volts after 24 hours charging whilst the other is only showing 11.04.


Thanks richard.
Looks like you have a duff battery. A good one should measure 12.5-12.8with no load. However , maybe you have a bad connection, so measure directly across the terminals. The fact that there is a difference is significant. Sorry, buy a new one.
__________________
Running around like a head with it's chicken cut off.
Limey Linda is offline   Reply With Quote
Old 17 March 2008, 16:41   #4
Member
 
Country: UK - England
Town: cornwall
Boat name: nothing
Make: rib eye 430
Length: 4m +
Engine: tatsu 50
MMSI: 666
Join Date: Mar 2006
Posts: 1,916
I find batteries that have just been on charge seem to read around 14.5 v and hold that for a while . Could be worth getting the other one checked
__________________
ian parkes is offline   Reply With Quote
Old 17 March 2008, 17:03   #5
Member
 
Country: UK - Wales
Town: Here
Boat name: doggypaddle
Make: Avon 5.4 Searider
Length: 5m +
Engine: yamaha 80
Join Date: Jul 2007
Posts: 1,107
sounds like a dead cell. 2.2 volts per cell is about right fully charged so 11 volts = 5 good cells one dead one.Look into the cells while its charging, they should be all gassing the same and look the same, pos plates chocolate brown and negatives slate grey.
you will probably find one cell either gassing more or less than the rest and the plates all grey and white, thats the dead un!
be careful not to wiggle the wires causing sparks or use a naked flame to look in the cells or you will get a dead eye too! battery gas is 2 parts hydrogen to one part oxygen, perfect stoichiometric mix for maximum bang!!
your other battery is likely OK if you get around 13.2 volts after its stood overnight after a thorough charging. you may get a false voltage when its come straight off charge 14-15V because of a phenomenon known as surface charge.
__________________
doggypaddle is offline   Reply With Quote
Old 17 March 2008, 20:44   #6
Member
 
richardjawilson's Avatar
 
Country: UK - England
Town: London, boat Dartmouth
Boat name: Lark
Make: Capelli Cap 32 WA
Length: 10m +
Engine: Yamaha 250x2
MMSI: 235096621
Join Date: Feb 2006
Posts: 189
Thanks for all your help. Have tested dodgy battery again and its down to 10.5v, so that one is for the bin. Other one is fine. Hopefully I will be out tomorrow afternoon for a quick spin !

regards richard
__________________

__________________
richardjawilson is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 18:18.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.