RV.Net Open Roads Forum: Tech Issues: Lithium batteries and alternator protection.

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tech Issues

Open Roads Forum  >  Tech Issues

 > Lithium batteries and alternator protection.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 8  
Prev  |  Next
Sponsored By:
theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 03/12/22 08:55pm Link  |  Quote  |  Print  |  Notify Moderator

CA Traveler wrote:

Also 13.2V would not be a issue for me as it indicates a charged battery and the alternator is only supplying chassis and converter loads. A higher voltage indicates the chassis battery is drawing amps so at least the DC-DC converter has less conversion losses.

Almost all vehicles for the past 15-20 years or so, use some kind of a smart charging system. The voltage from the alternator is controlled by the engine computer and can vary over a wide range.

Tom_M

New Hope, MN

Senior Member

Joined: 04/24/2011

View Profile


Offline
Posted: 03/13/22 03:31am Link  |  Quote  |  Print  |  Notify Moderator

I have had my Renogy 170ah lithium battery for 2 years and have had no issues with it hooked directly to the alternator.


Tom
2005 Born Free 24RB
170ah Renogy LiFePo4 drop-in battery 400 watts solar
Towing 1978 VW Bug convertible
Minneapolis, MN


CA Traveler

The Western States

Senior Member

Joined: 01/03/2004

View Profile


Offline
Posted: 03/13/22 08:16am Link  |  Quote  |  Print  |  Notify Moderator

theoldwizard1 wrote:

CA Traveler wrote:

Also 13.2V would not be a issue for me as it indicates a charged battery and the alternator is only supplying chassis and converter loads. A higher voltage indicates the chassis battery is drawing amps so at least the DC-DC converter has less conversion losses.

Almost all vehicles for the past 15-20 years or so, use some kind of a smart charging system. The voltage from the alternator is controlled by the engine computer and can vary over a wide range.
Does this apply to MH engines delivered w/o an alternator which is upgraded to a larger alternator due to the larger power demands? Is there any additional information on this subject?


2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland

Bob


theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 03/13/22 09:18am Link  |  Quote  |  Print  |  Notify Moderator

CA Traveler wrote:

theoldwizard1 wrote:


Almost all vehicles for the past 15-20 years or so, use some kind of a smart charging system. The voltage from the alternator is controlled by the engine computer and can vary over a wide range.
Does this apply to MH engines delivered w/o an alternator which is upgraded to a larger alternator due to the larger power demands? Is tbhere any additional information on this subject?

Smart charging started in cars but moved to all Ford produced vehicles fairly quickly. The size of the alternator did not matter.

What additional information do you want ? To see it in action, turn just the headlights on for about 5-10 minutes. Hook a multimeter directly to the battery. Start the MH and hold it at a high idle. The initial voltage will be in excess of 14V. It will drop within a few minutes. After about 5-10 minutes of high idle, the voltage will drop down to about 12.6V - 13.2V. This is lower than any conventional alternator/regulator.

S Davis

Western WA

Senior Member

Joined: 08/11/2005

View Profile


Offline
Posted: 03/13/22 11:55am Link  |  Quote  |  Print  |  Notify Moderator

theoldwizard1 wrote:

CA Traveler wrote:

Also 13.2V would not be a issue for me as it indicates a charged battery and the alternator is only supplying chassis and converter loads. A higher voltage indicates the chassis battery is drawing amps so at least the DC-DC converter has less conversion losses.

Almost all vehicles for the past 15-20 years or so, use some kind of a smart charging system. The voltage from the alternator is controlled by the engine computer and can vary over a wide range.


Not on 2009, 2013, 2019 GM 2500HD diesels, my last three trucks all have had steady voltage at about 14.2 no matter what. They must be in the almost none category.

One of my Redarc 50 amp chargers pulls 50 amps from the alternator and output is about 46 amps to the batteries, so on Redarc it looks like the rating is what is pulled from the alternator.

BFL13

Victoria, BC

Senior Member

Joined: 02/15/2006

View Profile



Posted: 03/13/22 12:21pm Link  |  Quote  |  Print  |  Notify Moderator

https://cdn.shopify.com/s/files/1/2204/8........which_alternator.pdf?9828243052323048027

Says the 50A Redarc has rating 50A output at 750 watts with 60A fuse for both input and output. 750/50 = 15v

see specs link here:

https://redarcelectronics.com/products/d........-input-50a-in-vehicle-dc-battery-charger


1. 1991 Oakland 28DB Class C
on Ford E350-460-7.5 Gas EFI
Photo in Profile
2. 1991 Bighorn 9.5ft Truck Camper on 2003 Chev 2500HD 6.0 Gas
See Profile for Electronic set-ups for 1. and 2.

time2roll

Southern California

Senior Member

Joined: 03/21/2005

View Profile



Good Sam RV Club Member


Posted: 03/13/22 12:54pm Link  |  Quote  |  Print  |  Notify Moderator

Tom_M wrote:

I have had my Renogy 170ah lithium battery for 2 years and have had no issues with it hooked directly to the alternator.
Any chance a measurement of the charging amps was noted? Please post if available.


2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
675w Solar pictures back up

CA Traveler

The Western States

Senior Member

Joined: 01/03/2004

View Profile


Offline
Posted: 03/13/22 02:28pm Link  |  Quote  |  Print  |  Notify Moderator

In that case my 09 RV, 14 Jeep and 19 Lincoln don't have smart chargers.

My understanding is smart chargers lower the voltage to compensate for the increased car electronic load and hence less alternator load. However the batteries still have to be first charged at higher voltage. So how does that translate into a MH with 2 larger battery banks and higher loads?

Tom/Barb

Oak Harbor, Wa

Senior Member

Joined: 10/16/2009

View Profile



Good Sam RV Club Member


Posted: 03/13/22 08:36pm Link  |  Quote  |  Print  |  Notify Moderator

BFL13 wrote:

Tom/Barb wrote:

This is what we did, A 30amp DC to DC charger gives you the ability to charge the coach battery bank while running the coach engine.
This limits the engine alternator to 30 AMPs thus prevents overheating the engine alternator....


Do you still believe that ?
Hope the OP doesn't .


Yes.
Our equipment is operating as it should, 2 years in, set IAW Victron's settings .
So why shouldn't I believe that?

Some folks wouldn't believe, even when the proof is in front of them.


2000 Newmar mountain aire 4081 DP, ISC/350 Allison 6 speed, Wrangler JL toad.

otrfun

On The Road

Senior Member

Joined: 09/08/2012

View Profile



Good Sam RV Club Member


Posted: 03/14/22 06:50am Link  |  Quote  |  Print  |  Notify Moderator

Tom/Barb wrote:

BFL13 wrote:

Tom/Barb wrote:

This is what we did, A 30amp DC to DC charger gives you the ability to charge the coach battery bank while running the coach engine.
This limits the engine alternator to 30 AMPs thus prevents overheating the engine alternator....
Do you still believe that ?
Hope the OP doesn't .
Yes.
Our equipment is operating as it should, 2 years in, set IAW Victron's settings .
So why shouldn't I believe that?

Some folks wouldn't believe, even when the proof is in front of them.
A 30a dc to dc charger producing only 20a of charge current indicates 1) a very inefficient dc to dc charger with only 66% conversion efficiency, 2) an installation experiencing excessive voltage drop due to undersized cabling or bad terminations, and/or 3) a 20a dc to dc charger that is improperly rated as a 30a charger.

Our 40a dc to charger outputs 40a of charge current with only a 43.5a draw on the alternator—-92% conversion efficiency. The manufacturer recommended 4 gauge for our run length. We used 2 gauge cabling to minimize voltage drop and maximize conversion efficiency.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 8  
Prev  |  Next

Open Roads Forum  >  Tech Issues

 > Lithium batteries and alternator protection.
Search:   Advanced Search

Search only in Tech Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:




© 2022 CWI, Inc. © 2022 Good Sam Enterprises, LLC. All Rights Reserved.