Good Sam Club Open Roads Forum: Tech Issues: New to lithium battery
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

 > New to lithium battery

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 3  
Next
lem55

Santa Maria,Ca USA

New Member

Joined: 05/23/2004

View Profile



Good Sam RV Club Member


Posted: 05/13/22 03:49pm Link  |  Quote  |  Print  |  Notify Moderator

Have a question which l hope you can help with. First my charge/converter went out and replaced with a 40 amp OEM unit. I know this unit is not designed to charge the lithium battery.
I needed to replace my batteries, so I invested in a 200 amp lithium
battery with a external charger designed to charge it.
And now for the question, will it hurt the lithium battery to be hooked
to the system when I am plugged into shore power. a long with that I have a old 100 watt solar charging system. Do I need to put in a disconnect switch. I had planned on charging with lithium charger.
I don't want to damage this very pricey battery.
Please help.

Lwiddis

Owens River area

Senior Member

Joined: 08/12/2016

View Profile



Good Sam RV Club Member

Offline
Posted: 05/13/22 04:16pm Link  |  Quote  |  Print  |  Notify Moderator

I charge my Lithium battery in only two ways…solar (95% of the time) and via a 10 amp Lithium AC to DC charger that I plug in separately from my TT, usually while driving.


Winnebago 2101DS TT & 2020 Chevy Silverado 1500 LTZ Z71, WindyNation 300 watt solar-Lossigy 200 AMP Lithium battery. Prefer boondocking, USFS, COE, BLM, NPS, TVA, state camps. Bicyclist. 14 yr. Army -11B40 then 11A - (MOS 1542 & 1560) IOBC & IOAC grad


3 tons

NV.

Senior Member

Joined: 03/13/2009

View Profile


Offline
Posted: 05/13/22 04:52pm Link  |  Quote  |  Print  |  Notify Moderator

When hooked up to shore power, just use one of these (Link):

https://www.amazon.com/Ampper-Battery-Disconnect-Isolator-Vehicles/dp/B07JYDY7FQ/ref=sxts_rp_s_a1_0?crid=1V4RUX6Y2YVRO&cv_ct_cx=battery+knife+switch&keywords=battery+knife+switch&pd_rd_i=B07JYDY7FQ&pd_rd_r=0afd5500-0ede-4cbd-a902-966165ee207e&pd_rd_w=DRC4v&pd_rd_wg=OzLnR&pf_rd_p=ae71c5d9-0355-41f0-ae0d-6fe5c47bc5dd&pf_rd_r=XXFHAMRTKRHDZ8FE0W1W&psc=1&qid=1652481232&sprefix=Battery+knife%2Caps%2C470&sr=1-1-5985efba-8948-4f09-9122-d605505c9d1e

Solar should not cause any difficulties because with Lithium (LFP) there’s no real need to charge it to a full 100% SOC (state of charge) like you would with a lead-battery, except for the ‘occasional’ cell-balancing regime - in fact, except for cell-balancing, it’s far better to avoid maintaining the battery at a full state of charge, and thanks to LFP’s far deeper discharge characteristics, you can just allow the solar to battery just ‘play’ somewheres between the upper and lower SOC span…However, because of LFP’s relatively flat voltage discharge plateau, determining SOC can be problematic, thus I’d recommend a quality lithium compatible SOC meter, something like a Victron ‘Smart-Shunt’ (smart phone compatible), or of equivalent make…

Charging LFP’s is simple, so long as ‘post, cell-balancing’ you don’t overcharge for an extended period of time…

I would also recommend (because of some stray info interlopers), that you endeavor to follow forum advice from those who have ‘actual’ hands-on LFP operational and ownership experience…JMHO Only…

3 tons

time2roll

Southern California

Senior Member

Joined: 03/21/2005

View Profile



Good Sam RV Club Member


Posted: 05/13/22 05:11pm Link  |  Quote  |  Print  |  Notify Moderator

Best to dig in and find the converter make and model and post for best answers.
Same with the solar. Need to know the charging voltage.

Most are actually quite compatible with drop in lithium batteries. Actually some lithium converters are worse than standard converters.

May as well post what battery was installed.


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

wa8yxm

Davison Michigan (East of Flint)

Senior Member

Joined: 07/04/2006

View Profile


Offline
Posted: 05/13/22 05:20pm Link  |  Quote  |  Print  |  Notify Moderator

First what OEM converter did you buy.
Second what is the charge/float voltage for your LI battery

As I recall (And I stress that As I recall part for I may recall incorrectly) LI's float and charge a couple points higher than Lead Acid.

Google says A fully charged 12V LiFePO4 battery will have a charging voltage of around 14.6 volts and a resting voltage of around 13.6 volts.

For Lead acid Google says: The typical charging voltage is between 2.15 volts per cell (12.9 volts for a 12V 6 cell battery) and 2.35 volts per cell (14.1 volts for a 12V 6 cell battery)

Which is not what I recall from earlier research. (I recall closer to LiFePO4 specs)

In either case I do not think the LI will be damaged by the OEM converter.


Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times


theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 05/13/22 06:06pm Link  |  Quote  |  Print  |  Notify Moderator

If the charger has reasonable amount of power for your 12V needs (lights and ... ?) Just get rid of the converter and wire the battery directly to the 12V distribution box. Plug your charger into a convenient outlet.

theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 05/13/22 06:09pm Link  |  Quote  |  Print  |  Notify Moderator

wa8yxm wrote:

Google says A fully charged 12V LiFePO4 battery will have a charging voltage of around 14.6 volts and a resting voltage of around 13.6 volts.

Why do people over think these things !

That is well within the range of 12VDC appliances.

Ditch the old converter and wire the battery to the DC distribution panel.

3 tons

NV.

Senior Member

Joined: 03/13/2009

View Profile


Offline
Posted: 05/13/22 06:23pm Link  |  Quote  |  Print  |  Notify Moderator

“Ditch the old converter and wire the battery to the DC distribution panel.…”

I’m not sure what this means?? …Since he merely replaced the previous battery, wouldn’t the LFP still be connected to the distribution panel??

3 tons

3 tons

NV.

Senior Member

Joined: 03/13/2009

View Profile


Offline
Posted: 05/13/22 06:29pm Link  |  Quote  |  Print  |  Notify Moderator

Goggles 14.6 volt figure merely refers to the upper charge limit before BMS protective cut-off…From my own experience, LFP’s are happy to charge even in the high thirteens…Just saying

3 tons

AllegroD

Outdare

Senior Member

Joined: 05/13/2003

View Profile



Posted: 05/13/22 07:13pm Link  |  Quote  |  Print  |  Notify Moderator

As others have said, you need to do some research. What is max input for your lithium batt? Can your charger be programmed to that max value?

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 3  
Next

Open Roads Forum  >  Tech Issues

 > New to lithium battery
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.