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Re: lithium batteries

Reply #25 –
Installing the batteries this weekend ..

Allan @ Bay Marine has been a great help. This is an early pic of my solar on other days

Re: lithium batteries

Reply #26 –
Here are your LIFEPO4 cell recommendations:

Discharge to no less than 2.5V
Charge to no more than 3.6V
Bottom balance to 2.5V. Get all the cells to hold at 2.5V, then charge normally.
Don't bother top balancing or balancing at anything less than 3V.
Store at 3.3V, or about 50% SOC (State of Charge).
To maximize battery life: 1. Operate battery between 80% and 20% SOC (State of Charge) 2. Charge and discharge between 40F and 90F degrees.
Strap them together so they don't bulge.

I use the Orion Jr. BMS. They are on sale for about $183 on eBay. Good insurance policy, but it takes a lot of research to engineer the connections properly. PM me for the connectors and crimp pins to use. The Orion Jr. BMS connects to a Windows Laptop via an inexpensive RS232 cable so your battery pack becomes "sentient" in that you read every cell voltage, pack current and pack SOC. It can also set alarms, relays, etc...

For my 12V pack (Four 400AH batteries) I charge with an iCharger 4010DUO intelligent RC charger.  It can charge, discharge, balance and send a storage charge to the batteries.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: lithium batteries

Reply #27 –
What is the best way to keep the alternator from overcharging? Where does the charge wire tie into the batteries?

Was going to run the batteries in pairs of 5 but now I am second guessing.. maybe just run in 4s and adjust the alternator? I have the dongle for the solar and the directions for the inverter, going to set them up but the alternator is my real question?

or disconnect it from the house for now

Re: lithium batteries

Reply #28 –

David,

This might answer some of your questions.

DIY Lithium Batteries: How to Build Your Own Battery Packs: Micah Toll:...

It's been well recommended on some of the lithium battery sites.

If you do get it please give us a review. :)

see ya
ken

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
The selected media item is not currently available.ken & dori hathaway & Big Agnes
🍺1992 U300 GrandVilla WTBI #4150 FOT FBP 2011
✨6V-92TA DDEC Parlor Coach 350HP Series 92
🏁2011 Nissan XTerra Pro-4X

Re: lithium batteries

Reply #29 –
Quote from: kenhat –
David,

This might answer some of your questions.

DIY Lithium Batteries: How to Build Your Own Battery Packs: Micah Toll:...

It's been well recommended on some of the lithium battery sites.

If you do get it please give us a review. :)

see ya
ken

I will give that book a try.. going to go with the 4s setup and i can always change it later.. going to disconnect the alternator to the house as I have solar so that shouldnt be an issue and adjust the charge perimeters .. Alternator is my only questionable charger.

Not sure what I need to make that end work.. Also does the house battery only charge from the inverter when plugged in or is there another charge box I need to work around? Kinda remember someone talking about a hum and maybe 2 boxes?
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: lithium batteries

Reply #30 –
Two things:
 (Definitions: House battery = Coach battery. Engine battery = Starting battery)

ALTERNATOR
I plan on disconnecting the alternator from LIFEPO4 Engine battery. I may use a 4LB lead acid VRLA battery for the alternator to charge, just for a third backup battery.

ENGINE BATTERY
For starting and running engine systems a 400AH LIFEPO4 battery will be used. It will be charged with the iCharger 4010Duo Smart charger, which will be powered by 115VAC through an IOTA 12V (DLS-12-30) power supply.

This battery is suitable as a deep-cycle House battery backup, since it is lithium.

BOOST CIRCUIT
Eliminated.

BACKUP POWER
The concept of the traditional diode-based circuit will be installed using two silicon (.6V drop) and one schottky (.3V drop) diodes. See schematic diagram below. Features:

1. 12Volt House power maintained in the event of house battery failure.
2. Independent smart charging of House and Engine lithium batteries. Includes SOC management and bottom balancing).
3. Solar, shore or generator power used for charging House and Engine batteries.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: lithium batteries

Reply #31 –
I have isolated my house and engine battery banks with a manual switch.  In the almost two years now, I have never needed house to alt charging.  Really don't like two battery types in circuit.  Not smart enough to do all of work you described.

Still use alt with engine of course as well as solar panel.

Boost circuit removed from driver side.  Larger capacity circuit can be used in either direction or combined from house battery compartment.  Ran 2/0 to selector from engine bank.

Allan is a great source.
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: lithium batteries

Reply #32 –
Sounds great. Here are photos of the engine battery system I will install next month.

The analog meter is the State of Charge indicator from the Orion Jr. BMS, with full scale equal 100%.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: lithium batteries

Reply #33 –
how many amps can I safely run through them? everything is connected and adjusted except the alternator.. 105 degrees out and hot..

when I run the microwave is it ok for them to drop below the 12v range? Or at anytime as long as it is a draw and not the actual sitting volts of the battery?

Re: lithium batteries

Reply #34 –
Something else I thought about.. How does the current flow from the generator? Through the inverter? Or is there a separate charger?

Re: lithium batteries

Reply #35 –
My 400AH lithiums can produce 3000Amps.

I recommend not charging Lithium with an alternator. Do it through a smart charger SPECIFICALLY designed for LIFEPO4, including individual cell monitoring. Don't buy into false claims that chargers can be set up to manage lithiums.

It's not about total pack voltage. A voltage down to 2.5 Volts per cell is acceptable, but each cell must be monitored and a low-voltage alarm or relay must disconnect the battery below this voltage.

I have designed my system to charge with 125VAC, so the inverter, genny, shore or solar can be used. I may design an emergency backup charging system through the alternator, which will limit charge current to about 20 amps, just to take it easy on the alternator.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: lithium batteries

Reply #36 –
Is a 50amp or larger charge ok? I set the PV for 20amps just dont know if its to little

Re: lithium batteries

Reply #37 –
David one last comment from me on this one.  I agree on the alternator as mentioned before but some of your tech issues can be answered on Victron tech blog for your specific equipment.  If you want to use your alternator take a look at the Cyrix for example.  Those systems were designed to be used for lithium charging.  Now that may very well be because their battery's onboard systems interface by proprietary design but I haven't seen anything to support that thought. 

You may want to examine AMS new control card.  I spoke with Allan late last year and he may be reselling I am not sure.  I attached a couple of schematics.  One stand alone and one integrated.

Muttering from the wilderness as you guys are way above my weight class.  Good luck!


George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: lithium batteries

Reply #38 –
Two comments:
 
1. Charge Rate
a. My 48V 180AH solar lithium charged at:
  Shore or genny power: 15 Amps, or about 750 watts
  Solar power:  30 Amps, or about 1500 watts

b. My 12V 400AH lithium will be charged at anywhere between 1 and 30 amps, depending on the plentifullness of the power source: E.g. Solar vs shore power.

2. Victron and AM solar
These are great companies. If you have big bucks, I highly recommend their products. They sell quality products that will increase the value of your rig. I am a "value" investor, and chose not to pay 3x for products that I could procure, engineer and maintain myself. As the old bromide says "You get what you pay for".

If you are managing charge of BYOB (Bring Your Own (Lithium) Battery) cells, I do not believe Victron or AM Solar can help you. Cell-based monitoring mandatory a must to prevent cell damage and start possibly a fire.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: lithium batteries

Reply #39 –
Our coach has a 600 AH LiFePo4 bank from AM solar with all Victron components. The BMS is Victron. The parameters are for Victron batteries only. You must find out what  your specific battery needs are to safely charge and maintain them. BMS is essential for lithium.
Last week we ran down our batteries by accident when we though we were on shore power but forgot to sent the transfer switch to shore ( we have a manual transfer switch for safety) The BMS shut down the system. With no BMS, permanent damage would have happened. Good luck with your setup.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: lithium batteries

Reply #40 –
Quote from: Bob and Julie –
Our coach has a 600 AH LiFePo4 bank from AM solar with all Victron components. The BMS is Victron. The parameters are for Victron batteries only. You must find out what  your specific battery needs are to safely charge and maintain them. BMS is essential for lithium.
Last week we ran down our batteries by accident when we though we were on shore power but forgot to sent the transfer switch to shore ( we have a manual transfer switch for safety) The BMS shut down the system. With no BMS, permanent damage would have happened. Good luck with your setup.

How did that happen with Solar?

Re: lithium batteries

Reply #41 –
Bob, sounds like we have a similar system.  My earlier reference was to the settings for the Multipass and the solar controller.  These have settings for non Victron lithium as well.
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P
 

Re: lithium batteries

Reply #42 –
Solar can't keep up with the a/c. We had tied into our home shore power that I had installed, and the 2 a/cs were pulling more than the 30 amp one I plugged into. Had to switch it to the 50 amp. With Victron you can limit the amount of amps pulled and I could have set it for 25, but it was at 30, wife didn't know that so it tripped the breaker. But the BMS saved the day.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired