Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 17-06-2014, 10:19   #151
Moderator
 
sailorchic34's Avatar

Cruisers Forum Supporter

Join Date: Feb 2011
Location: SF Bay Area
Boat: Islander 34
Posts: 4,812
Re: Mixing Battery types in 1 Bank

Actually 13.8V and 14.4V would be correct for lead acid batteries.

13.4 and 14.1 is what gels are normally charged at. That would not hurt the LA ether, though may not charge the LA all the way.

It's possible that your battery charger has a equalizing mode which raises the voltage once a month to desulfate the plates.

Another cause of out gassing is a shorted/bad cell in on battery.

BTW Colemj beat me toit and is correct. Absorption for LA can go anywhere from 14.4v to 14.8v. Most chargers are set by default at 14.4V.
__________________

__________________
sailorchic34 is offline   Reply With Quote
Old 17-06-2014, 10:24   #152
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by sailinglegend View Post
I'm sorry if some didn't understand my expanded water tank analogy, but this is a standard Nigel Calder explanation of battery charge acceptance, but he uses membranes within the tank not additional tanks with a restrictive pipe in between. So if you disagree with my analogy then argue with Mr Calder. I have taken his analogy with two tanks with different internal resistances, or different membranes, and I have even joined them together with a very large pipe. Some people here just do not read posts properly before jumping in with both feet. That is plain rudeness. Nowhere did I suggest these internal tanks were cell analogies, they are representing the difference between the surface areas of the plates and the internal areas.
You know, I had a peek at Calder's book and the explanation you are citing.

He not only was discussing series cells (as I stated), he was discussing an individual cell. Like you state in your last sentence, he was describing an analogy for a high surface charge to migrate throughout a thick plate.

His analogy has nothing at all to do with with mixing batteries, or even putting two of the same type of batteries together.

My description the water tank is correct - if used to describe two batteries (of any LA type), then the pipe connecting those batteries is large in comparison to the fill and drain pipes.

Your expansion of Calder's description, as well as your application to multiple batteries, is incorrect. I don't have to argue it with Calder, because I agree with his analogy (although I always find water tank analogies more confusing than the actual electrical models they are trying to represent).

Mark
__________________

__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 17-06-2014, 10:28   #153
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Mixing Battery types in 1 Bank

Again, I don't understand the "boost" function, but 13.8V would be a bit high to float FLA's - if that is what the lower number means. Probably would not do much damage floating it there, but it is a bit high.

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 17-06-2014, 10:31   #154
Eternal Member
 
monte's Avatar

Cruisers Forum Supporter

Join Date: Jul 2011
Location: Australia
Boat: Lagoon 400
Posts: 3,650
Images: 1
Re: Mixing Battery types in 1 Bank

OK thanks, though that's not helping much if the cause of the smell isn't related to the charging levels.
Heres a pic from the manual and details below.
The smell is rotton egg gas and the electricians working on board agreed is is pretty strong.


BOOST in ON position
With this setting the CPS3 charger delivers a 3-state load curve IUoU: BOOST, Absorption, Floating

U Boost: BOOST voltage (see table above)
U Floating: Floating voltage (see table above: voltage with no BOOST)
T Boost: BOOST maximum duration (see table above)
Boost phase: starts up automatically when the charger is turned on if the battery is flat. The current is
then at maximum output.
Absorption phase: begins when the voltage has reached the maximum BOOST level. The current level
starts falling.
These two phases combined last a maximum of TBOOST (depending on setting). If the current falls below
20% of rated current, the floating phase automatically kicks in. Duration and current intensity depend on
how charged the battery is.
Floating phase: starts after TBOOST or if output current has reached 20% of the charger's rated current.
The voltage switches to the Floating value and the rated current continues to drop.
Attached Thumbnails
Click image for larger version

Name:	dip switches.JPG
Views:	47
Size:	75.7 KB
ID:	83317  
__________________
monte is offline   Reply With Quote
Old 17-06-2014, 10:35   #155
Eternal Member
 
monte's Avatar

Cruisers Forum Supporter

Join Date: Jul 2011
Location: Australia
Boat: Lagoon 400
Posts: 3,650
Images: 1
Re: Mixing Battery types in 1 Bank

Heres a pic of the boost function
Attached Thumbnails
Click image for larger version

Name:	boost.JPG
Views:	53
Size:	39.3 KB
ID:	83318  
__________________
monte is offline   Reply With Quote
Old 17-06-2014, 10:47   #156
Moderator
 
sailorchic34's Avatar

Cruisers Forum Supporter

Join Date: Feb 2011
Location: SF Bay Area
Boat: Islander 34
Posts: 4,812
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by colemj View Post
You know, I had a peek at Calder's book and the explanation you are citing.

He not only was discussing series cells (as I stated), he was discussing an individual cell. Like you state in your last sentence, he was describing an analogy for a high surface charge to migrate throughout a thick plate.

His analogy has nothing at all to do with with mixing batteries, or even putting two of the same type of batteries together.

My description the water tank is correct - if used to describe two batteries (of any LA type), then the pipe connecting those batteries is large in comparison to the fill and drain pipes.

Your expansion of Calder's description, as well as your application to multiple batteries, is incorrect. I don't have to argue it with Calder, because I agree with his analogy (although I always find water tank analogies more confusing than the actual electrical models they are trying to represent).

Mark
Boy's Boys.... Be nice.

I've never read Calders book, but being an engineer who wrote a hydraulic analysis program ages ago I know a thing or two about piping and hydraulics.

Piping like electrical cable has an internal resistance to flow based on the size of the pipe and flow rate through it. Pretty much just like electrons and wire, though without inductance.

Like electrons, water travels the path of least resistance. So you will get unbalanced flow between batteries with with conductors (wires) of different lengths. You will also get different acceptance rates based on the internal resistance to the batteries or tanks. Water tanks with internal bladders set at different pressures will accept water at different rates.

Nothing tells the electrons which battery to go to, except cable resistance and battery resistance. Thats why even with the same battery types as the OP was talking about, but of different ages, the internal resistance would not be the same. This as resistance rises as batteries age too.

OK that's a bit simplistic as there are other factors too with electron flow and battery aging too.
__________________
sailorchic34 is offline   Reply With Quote
Old 17-06-2014, 10:48   #157
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Mixing Battery types in 1 Bank

OK, they are just using uncommon terms for "bulk" and "absorption". "Boost" would be what is normally referred to as "Bulk" (or even more properly "absorption 1"), and "Off" would be what is normally referred to as "float".

Your manual has mixed up the proper settings for Gel and FLA in its instructions. You should be using the Gel settings as they are stated in the manual, and I feel sorry for anyone with Gel batteries who have used these instructions.

Again, that float voltage is a bit higher than most recommend, but won't really do much harm.

I don't know why you are smelling rotten eggs. If it truly is hydrogen sulfide, then that is poisonous and indicates your batteries are severely damaged. They will probably be hot, not have much water and boiling like mad before HS is produced.

I suspect that what you are smelling is the result of fine sulfuric acid vapors landing on your nasal mucous membrane. This will also smell like rottten eggs, but not be indicative of poison or damaged batteries.

Since the manual is wrong on the Gel/FLA settings, is it possible it also has the FLA setting wrong? Did you actually measure the charging voltage at 14.4V at the battery terminals? If it is 15.1V because of another mistake in the manual, you may be vigorously boiling them and releasing sulfuric acid vapors.

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 17-06-2014, 10:49   #158
Eternal Member
 
monte's Avatar

Cruisers Forum Supporter

Join Date: Jul 2011
Location: Australia
Boat: Lagoon 400
Posts: 3,650
Images: 1
Re: Mixing Battery types in 1 Bank

A bit confused about the not smelling rotton egges comment though. I understood
"Over-charging a lead acid battery can produce hydrogen-sulfide. The gas is colorless, very poisonous, flammable and has the odor of rotten eggs."
So is it correct to assume the float charge of 13.8 instead of 13.4 was enough to cause gassing? Or the absorption at 14.4 instead of 14.1 was the problem? Or...I still have a problem unresolved...
BTW, currently the battery monitor states 13.95V
__________________
monte is offline   Reply With Quote
Old 17-06-2014, 10:50   #159
Moderator
 
sailorchic34's Avatar

Cruisers Forum Supporter

Join Date: Feb 2011
Location: SF Bay Area
Boat: Islander 34
Posts: 4,812
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by monte View Post
Heres a pic of the boost function
Ah so boost is just bulk charging to 13.8V then absorption charging to 14.4. So boost is the same as bulk charge.
__________________
sailorchic34 is offline   Reply With Quote
Old 17-06-2014, 10:51   #160
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by sailorchic34 View Post
I've never read Calders book
We were discussing a specific analogy in his book in terms of how he applied it and what he applied it to.

The rest of what you wrote didn't pertain to this specific analogy at all.

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 17-06-2014, 10:55   #161
Moderator
 
sailorchic34's Avatar

Cruisers Forum Supporter

Join Date: Feb 2011
Location: SF Bay Area
Boat: Islander 34
Posts: 4,812
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by monte View Post
A bit confused about the not smelling rotten eggs comment though. I understood
"Over-charging a lead acid battery can produce hydrogen-sulfide. The gas is colorless, very poisonous, flammable and has the odor of rotten eggs."
So is it correct to assume the float charge of 13.8 instead of 13.4 was enough to cause gassing? Or the absorption at 14.4 instead of 14.1 was the problem? Or...I still have a problem unresolved...
BTW, currently the battery monitor states 13.95V
Actually even 14.4V should not cause out gassing. Either the charger was doing an equalizing or you might having a bad cell in one battery. Not uncommon.

To find the bad cell, turn off the charger and disconnect the Ground cable from each parallel battery. Lt it sit for a 1/2 hour then measure voltage at each battery with a VO meter. if both batteries have the same voltage, somewhere around 12.8V life it good. IF one battery reads low, say 12V or 11. something then you have a bad battery.
__________________
sailorchic34 is offline   Reply With Quote
Old 17-06-2014, 10:55   #162
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by sailorchic34 View Post
Ah so boost is just bulk charging to 13.8V then absorption charging to 14.4. So boost is the same as bulk charge.
I read it as boost is bulk and absorption - run up to 14.4V, keep it there based on a time calculated by some type of "turbo boost" (??!!??), then drop to float at 13.8V.

If monte comes back and tells me there is also a "super turbo boost" that modifies everything, I'm outta here!

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 17-06-2014, 10:59   #163
Moderator
 
sailorchic34's Avatar

Cruisers Forum Supporter

Join Date: Feb 2011
Location: SF Bay Area
Boat: Islander 34
Posts: 4,812
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by colemj View Post
We were discussing a specific analogy in his book in terms of how he applied it and what he applied it to.

The rest of what you wrote didn't pertain to this specific analogy at all.

Mark
You say the sweetest things....

Actually I had reread SL's posting about the tanks, before posting, so pretty sure I understood his position anyway. Which I oddly find to be correct.
__________________
sailorchic34 is offline   Reply With Quote
Old 17-06-2014, 10:59   #164
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by monte View Post
A bit confused about the not smelling rotton egges comment though. I understood
"Over-charging a lead acid battery can produce hydrogen-sulfide. The gas is colorless, very poisonous, flammable and has the odor of rotten eggs."
So is it correct to assume the float charge of 13.8 instead of 13.4 was enough to cause gassing? Or the absorption at 14.4 instead of 14.1 was the problem? Or...I still have a problem unresolved...
BTW, currently the battery monitor states 13.95V
Actually, over-charging a FLA to produce HS gas is a difficult thing to do. It will require a huge dump of current, the battery will need to be very hot, and the cells will probably be dry or very low. In other words, to produce HS gas, you need a considerably damaged battery taking high currents at high voltages from a charging source. And HS is heavier than air, so unlikely you would be noticing it just in the general area.

Float at 13.8V and absorption at 14.4V would not be a problem unless you do have a very damaged cell (and even then, only maybe).

Again, most likely sulfuric acid vapors, and not hydrogen sulfide.

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 17-06-2014, 11:00   #165
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Mixing Battery types in 1 Bank

Quote:
Originally Posted by sailorchic34 View Post
You say the sweetest things....

Actually I had reread SL's posting about the tanks, before posting, so pretty sure I understood his position anyway. Which I oddly find to be correct.
Did you read Calder's?

Mark
__________________

__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Reply

Tags
battery

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Anchor types & Bottom types pbiJim Anchoring & Mooring 31 03-06-2014 21:38
Mixing 'types' of AGM batts?? John Drake Electrical: Batteries, Generators & Solar 18 13-12-2006 18:47



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 11:39.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.