Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 10-06-2012, 10:47   #76
Marine Service Provider

Join Date: Dec 2003
Location: South Carolina
Boat: Philip Rhodes Custom
Posts: 395
Re: Battery Cabling for Parallel Bank

DO NOT CHARGE AFTER ADDING WATER, YOU WILL DESTROY THEM.

Some advise on restoring batteries that have run dry.
The resulting electrolyte after boiling off the water is VERY concentrated, thick and high density sitting on the bottom of the plates.
When you add distilled water it will float on top of the concentrated electrolyte and not mix. It can take weeks before natural mixing will equalize the concentration. If you apply a hard charge under these conditions you will destroy the batteries.
Getting the electrolyte back to a uniform density can take TIME, avoid the temptation to charge immediately.
Mechanical motion (side to side parallel to the plates) can help but usually not practical.
If it is a sealed battery, CAREFULLY try inverting it for a day.
A heat lamp applied to one side of the battery will create some circulation as the liquid rises on the hot side and rotates to the cool side.
If you don't have the time to wait you can put your charger on the equalize setting or maximu charge rate and then just run it for 5 minutes every hour. What you are trying to do is create thermal unbalance and small bubbles to stir up the electrolyte and circulate the concentrate up into the water but minimize transfer of plate materieals in the unbalanced state.
A hydromoter can be very helpful to evaluate your progress. Take a reading after you add the distilled water which will reveal how little it has mixed, then once a day to plot your recovery progress. When progress tapers off to a minimum you can then attempt a normal charge. An equalization charge at THIS stage will be very beneficial in creating bubbles to stir up the eletrolyte.

Good luck. I discovered this the HARD way.
__________________

__________________
Andina Marie is offline   Reply With Quote
Old 13-06-2012, 04:21   #77
Registered User
 
Rustic Charm's Avatar

Join Date: Jun 2011
Location: Tasmania, Australia
Boat: Bieroc 36 foot Ketch
Posts: 4,898
Re: Battery Cabling for Parallel Bank

Quote:
Originally Posted by Andina View Post
DO NOT CHARGE AFTER ADDING WATER, YOU WILL DESTROY THEM.

Some advise on restoring batteries that have run dry.
The resulting electrolyte after boiling off the water is VERY concentrated, thick and high density sitting on the bottom of the plates.
When you add distilled water it will float on top of the concentrated electrolyte and not mix. It can take weeks before natural mixing will equalize the concentration. If you apply a hard charge under these conditions you will destroy the batteries.
Getting the electrolyte back to a uniform density can take TIME, avoid the temptation to charge immediately.
Mechanical motion (side to side parallel to the plates) can help but usually not practical.
If it is a sealed battery, CAREFULLY try inverting it for a day.
A heat lamp applied to one side of the battery will create some circulation as the liquid rises on the hot side and rotates to the cool side.
If you don't have the time to wait you can put your charger on the equalize setting or maximu charge rate and then just run it for 5 minutes every hour. What you are trying to do is create thermal unbalance and small bubbles to stir up the electrolyte and circulate the concentrate up into the water but minimize transfer of plate materieals in the unbalanced state.
A hydromoter can be very helpful to evaluate your progress. Take a reading after you add the distilled water which will reveal how little it has mixed, then once a day to plot your recovery progress. When progress tapers off to a minimum you can then attempt a normal charge. An equalization charge at THIS stage will be very beneficial in creating bubbles to stir up the eletrolyte.

Good luck. I discovered this the HARD way.
ahhh crap, I've only just noticed your post.. thanks though. the way I'm going I'd better budget for some new batteries.
__________________

__________________
Rustic Charm is offline   Reply With Quote
Old 13-06-2012, 04:26   #78
Registered User
 
Rustic Charm's Avatar

Join Date: Jun 2011
Location: Tasmania, Australia
Boat: Bieroc 36 foot Ketch
Posts: 4,898
Re: Battery Cabling for Parallel Bank

Quote:
Originally Posted by Jbaffoh View Post
I just downloaded the manual, and didn't see that mentioned anywhere.

What puzzles me is that you've been seeking battery advice here for 10 days, and working on your system for 8 weeks. During that time you didn't check your batteries and charger, and you didn't even read the manual until now? That's a good way to murder a battery bank.
Well, it's there in the instructions!
And no, I not been working on the system for 8 weeks at all. I've actually been overalling the engine and now I'm on to the battery box. I've simply been preparing for wiring it all up again.
Thanks for the encouragement.
__________________
Rustic Charm is offline   Reply With Quote
Old 13-06-2012, 05:52   #79
Commercial Member
 
Mark Johnson's Avatar

Cruisers Forum Supporter

Join Date: Sep 2009
Location: New Bern NC
Boat: Searunner 34 Trimaran
Posts: 1,565
Re: Battery Cabling for Parallel Bank

I use solar panels, 100%, to bring back my 340 Ah bank = ( two Trojan L-14s @ 6V ea)...

If sized correctly, as I do, where the batteries are only cycled about 10% down daily, then brought back EACH day through Bulk, absorption, and float, then your batteries lifespan is WAY more than a decade, (perhaps two), and the line V remains higher, making your more sensitive electronics happy.

By having TWICE the needed solar production available (anchored out on a normal sunny day), then even on cloudy days, we get back to 100% by the end of the day, with previously mentioned advantages.

After 40 years building boats, including my own, and 15 years as a liveaboard cruiser, (with thousands of nights on the hook), I have found my fully equipped "comfortable" home's electrical systems to be the most reliable aspects of the boat. The wiring harness is part of the reason too...

We Have Radar, watermaker, SSB, refrigeration, pressure water, dozens of fans and lights, etc... We only use about 40 Ah/day on average, and need to crank the engine for power (for 45 minutes or so)... < 10 days/year!

It is true that most folks find that keeping their batteries' top off point at a max of 90% is more practical, because of the inordinate time required to get that last 10%.

It is also true that, for them, this saves precious fossil fuels, (while shortening battery & electronics' lives).

It is, however, an often repeated "myth" that it needs to be this way... If you spend MOST of your time and money on reducing energy consumption, have a correctly sized solar array & battery bank, GOOD batteries and wiring techniques, (for "0" losses), and know how to maintain the system... then you should have decades of reliable, mostly fossil fuel free, energy production.

From what I read, almost everyone, including most books on the subject, are simply not doing what has worked so well for me since I started cruising "solar supplied self sufficient" in the 70s. I haven't the time to repeat it all in detail here, but my past posts go into the hows & whys, or for a verbal description, If you go to OutRigMedia.com and look at "conversations with Jim Brown", there is a conversation between Jim & I where I explain the concept.

It requires doing EVERYTHING different from the way we live on land, but you CAN have all of the comforts, (short of air conditioning). You can have it all self sufficient (95% of the time), reliable, and solar powered as well.

Best regards...

M.
Attached Thumbnails
Click image for larger version

Name:	P8290437 (2) - Copy.jpg
Views:	68
Size:	414.0 KB
ID:	42213   Click image for larger version

Name:	080_80_00.JPG
Views:	67
Size:	118.4 KB
ID:	42214  

Click image for larger version

Name:	086_86_00 - Copy.JPG
Views:	77
Size:	196.2 KB
ID:	42215   Click image for larger version

Name:	P3140595.JPG
Views:	69
Size:	77.9 KB
ID:	42217  

Attached Images
 
__________________
"Let us be kind to one another, for everyone you meet is fighting a hard battle".
Mark Johnson is offline   Reply With Quote
Old 13-06-2012, 07:41   #80
Registered User

Join Date: Feb 2011
Posts: 238
Re: Battery Cabling for Parallel Bank

Quote:
Originally Posted by tedsherrin View Post
Well, it's there in the instructions!
And no, I not been working on the system for 8 weeks at all. I've actually been overalling the engine and now I'm on to the battery box. I've simply been preparing for wiring it all up again.
Thanks for the encouragement.
Sorry Ted. You're definitely incurring more than your share of battery woes. For a minute, I was wondering if your posts were sincere.
__________________
Jbaffoh is offline   Reply With Quote
Old 13-06-2012, 07:43   #81
Marine Service Provider
 
Tony B's Avatar

Join Date: Jul 2011
Location: Presently in Rogersville, Al
Boat: Mainship 36 Dual Cabin
Posts: 695
Question.....

While we are on the subject of Batteries………..I currently have 2 house batteries, I am not sure of their age or condition and I won’t be able to check them for a while so let’s make this a generic question.
1). If I want a total of 4 house batteries in parallel can I just add 2 more based on the fact that they seem OK?
2). How much will the old batteries pull down the new ones?
3). Do I need to add all new batteries?
4). If my charger can handle multiple battery banks, should the old batts be a separate bank from the new batts?
5). If my charger will allow for multiple battery banks, do I have to split my DC system?
Thanks in advance
__________________
Tony B is offline   Reply With Quote
Old 13-06-2012, 07:56   #82
Registered User

Join Date: Feb 2011
Posts: 238
Re: Battery Cabling for Parallel Bank

Quote:
Originally Posted by Mark Johnson View Post
I use solar panels, 100%, to bring back my 340 Ah bank = ( two Trojan L-14s @ 6V ea)...

If sized correctly, as I do, where the batteries are only cycled about 10% down daily, then brought back EACH day through Bulk, absorption, and float, then your batteries lifespan is WAY more than a decade, (perhaps two), and the line V remains higher, making your more sensitive electronics happy.
M.
I'm glad to see somebody else who doesn't treat their batteries as disposable items! Proper care and feeding through an inexpensive solar setup is MUCH cheaper than prematurely replacing banks because of abuse.
__________________
Jbaffoh is offline   Reply With Quote
Old 13-06-2012, 08:11   #83
Registered User

Join Date: Feb 2011
Posts: 238
Re: Question.....

Quote:
Originally Posted by Tony B View Post
While we are on the subject of Batteries………..I currently have 2 house batteries, I am not sure of their age or condition and I won’t be able to check them for a while so let’s make this a generic question.
1). If I want a total of 4 house batteries in parallel can I just add 2 more based on the fact that they seem OK?
2). How much will the old batteries pull down the new ones?
3). Do I need to add all new batteries?
4). If my charger can handle multiple battery banks, should the old batts be a separate bank from the new batts?
5). If my charger will allow for multiple battery banks, do I have to split my DC system?
Thanks in advance
I am not an electrical engineer, and I am not in the business of installing or repairing electrical systems in boats every day as some other posters here. However, I spent years as a mechanic, and more years as a first mate on a commercial fishing boat, before wrapping a tie around my neck and specializing in the defense of product designers and manufacturers in court. Meanwhile, I have owned and performed my own repairs on boats my entire life. So the following advice is worth exactly what you paid for it.

1. If you do, the bank will only be as good as your worst battery.

2. Depends on their condition.

3. That's the best, but costliest solution.

4. That's what I would do. Better yet, replace the old batteries and make a large bank of all-new identical batteries. Then again, if the old batteries still have plenty of life in them, use them as a second bank.

5. Not sure what you mean. Just use a switch to switch from one bank or the other.

Edit: No. 4 does not depend on whether your charger can handle separate banks. As long as each bank is of the same chemistry, i.e. flooded, agm, gel, etc., you can send all charging sources to the main bank, and use an echo charger or ACM to charge the second bank.
__________________
Jbaffoh is offline   Reply With Quote
Old 13-06-2012, 08:28   #84
Marine Service Provider
 
Tony B's Avatar

Join Date: Jul 2011
Location: Presently in Rogersville, Al
Boat: Mainship 36 Dual Cabin
Posts: 695
Re: Question.....

Quote:
Originally Posted by Jbaffoh View Post
4. That's what I would do. Better yet, replace the old batteries and make a large bank of all-new identical batteries. Then again, if the old batteries still have plenty of life in them, use them as a second bank.

Edit: No. 4 does not depend on whether your charger can handle separate banks. As long as each bank is of the same chemistry, i.e. flooded, agm, gel, etc., you can send all charging sources to the main bank, and use an echo charger or ACM to charge the second bank.
Thanks J

One more question.....What is an echo charger and an ACM?
__________________
Tony B is offline   Reply With Quote
Old 13-06-2012, 08:30   #85
Registered User

Join Date: Feb 2011
Posts: 238
Re: Question.....

Quote:
Originally Posted by Tony B View Post
Thanks J

One more question.....What is an echo charger and an ACM?
An ACM is a typo. It should be ACR, or Automatic Charging Relay.

Google Xantrex for info about echo chargers. Google Blue Sea Systems for ACR's.
__________________
Jbaffoh is offline   Reply With Quote
Old 13-06-2012, 10:37   #86
Marine Service Provider

Join Date: Dec 2003
Location: South Carolina
Boat: Philip Rhodes Custom
Posts: 395
Re: Question.....

Quote:
Originally Posted by Tony B View Post
While we are on the subject of Batteries………..I currently have 2 house batteries, I am not sure of their age or condition and I won’t be able to check them for a while so let’s make this a generic question.
1). If I want a total of 4 house batteries in parallel can I just add 2 more based on the fact that they seem OK?
2). How much will the old batteries pull down the new ones?
3). Do I need to add all new batteries?
4). If my charger can handle multiple battery banks, should the old batts be a separate bank from the new batts?
5). If my charger will allow for multiple battery banks, do I have to split my DC system?
Thanks in advance
I am an electrical engineer with 50+ years of experience, 25 of those on boats and 14 as a live-aboard.

1) Yes you can add new batteries in parallel with the old one and total capacity will be the new ones plus what there was left in the old ones. The myth that capacity is limited to the weakest one only applies to batteries in series, not batteries in parallel.

2) Old batteries do not "pull down" the new ones. They are connected together and all at the SAME voltage. There may be some battery to battery current flow the first time you connect them together and it could even be from the old ones to the new ones depending on charge level. However after a minute they will all be at the same voltage and no current flows.

Sooner or later old batteries die and sometimes they die with a shorted cell. When that happens the bad battery will pull charge from the good ones trying to charge the bad cell but that does not do any harm to the good ones. The bad one will prevent the good ones from charging and draw your attention to the problem. Replace the bad one and you are back in business.

3) No they don't all have to be new. If the old ones still have capacity you don't need to waste that capacity. The only downside is for the total space and weight, brand new batteries would have more capacity but that will drop with age anyhow.

4. There is no advantage in charging old and new batteries separately.

5. If you have a multi output charger use the separate outputs for battery banks that are separate for application purposes. If you have unused outputs connect them together on the largest bank.
__________________
Andina Marie is offline   Reply With Quote
Old 13-06-2012, 11:12   #87
Registered User

Join Date: Feb 2011
Posts: 238
Re: Question.....

Quote:
Originally Posted by Andina View Post
I am an electrical engineer with 50+ years of experience, 25 of those on boats and 14 as a live-aboard.

1) Yes you can add new batteries in parallel with the old one and total capacity will be the new ones plus what there was left in the old ones. The myth that capacity is limited to the weakest one only applies to batteries in series, not batteries in parallel.

4. There is no advantage in charging old and new batteries separately.

5. If you have a multi output charger use the separate outputs for battery banks that are separate for application purposes. If you have unused outputs connect them together on the largest bank.
Sorry about that--I told you you get what you pay for!

Andina is right about the parallel/serial point. I knew that, but my caffeine had not kicked in, and my head is in a brief as we type.

The bit about no advantage to charging old and new batteries separately is debatable. It depends on how smart your charger is.
__________________
Jbaffoh is offline   Reply With Quote
Old 13-06-2012, 12:49   #88
Marine Service Provider

Join Date: Dec 2003
Location: South Carolina
Boat: Philip Rhodes Custom
Posts: 395
Re: Battery Cabling for Parallel Bank

There is no setting on your charger for "OLD" or "NEW" batteries, they all get charged the same way. The internal resistance of the individual batteries will distribute the incoming charge current in direct proportion to the battery capacity so you can't over charge a weak battery while fully charging a strong one. Eventually the voltage on them all will reach the end of the bulk threshold and switch to the next stage. A charger doesn't know or care if there are batteries in parallel, all it sees is a battery load and charges it.

While chemistry settings and charging regimens are available on modern chargers, all they do is decide how fast to charge and what the safe threshold voltage is. If you have mixed batteries in parallel you have to set the charger for the most forgiving battery type. They will still all get charged but it may take a few minutes longer if you have to use a lower setting to protect the weaker battery(ies).
__________________
Andina Marie is offline   Reply With Quote
Old 13-06-2012, 13:11   #89
Registered User

Join Date: Feb 2011
Posts: 238
Re: Battery Cabling for Parallel Bank

Quote:
Originally Posted by Andina View Post
There is no setting on your charger for "OLD" or "NEW" batteries, they all get charged the same way. The internal resistance of the individual batteries will distribute the incoming charge current in direct proportion to the battery capacity so you can't over charge a weak battery while fully charging a strong one. Eventually the voltage on them all will reach the end of the bulk threshold and switch to the next stage. A charger doesn't know or care if there are batteries in parallel, all it sees is a battery load and charges it.

While chemistry settings and charging regimens are available on modern chargers, all they do is decide how fast to charge and what the safe threshold voltage is. If you have mixed batteries in parallel you have to set the charger for the most forgiving battery type. They will still all get charged but it may take a few minutes longer if you have to use a lower setting to protect the weaker battery(ies).
Yeah, I'm pretty sure we'll see some dissent on this one.
__________________
Jbaffoh is offline   Reply With Quote
Old 14-06-2012, 03:46   #90
Nearly an old salt
 
goboatingnow's Avatar

Cruisers Forum Supporter

Join Date: Jun 2009
Posts: 13,649
Images: 3
Quote:
Originally Posted by Jbaffoh

Yeah, I'm pretty sure we'll see some dissent on this one.
Nope andina is right. You can of course connect old and together. It's often not recommended mainly as a precaution, but of course it works fine and the charger just charges the bank.

Dave
__________________

__________________
Check out my new blog on smart boat technology, networking and gadgets for the connected sailor! - http://smartboats.tumblr.com
goboatingnow 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




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 05:57.


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.