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Topic: Lithium house battery generator starting (Read 849 times) previous topic - next topic

Lithium house battery generator starting

I know many of you already thought through this process so I'd be grateful for your thoughts.

I am looking at either the LiTime 280ah  deep cycle or 300ah lithium battery to replace my current 8D flooded lead acid house battery. Both of these batteries are declared to be 200a max draw batteries. In reading the companies materials I saw that neither are approved for starting any engine.  I understand the issue that most lithium batteries are not designed to provide CCA. How have you taken that into consideration for generator starts as well as the use of the boost switch for engine starting?

Our coach is a 92 U240 with a 6500 propane generator and a Cat 3116 engine.

Thank you for your advice.

Michael
Michael & Ginny
Frankfort, KY
1992 U240 GV Build #4116
2007 Mini Cooper

Re: Lithium house battery generator starting

Reply #1 –

I had 6 100Ah lithium house batteries for 5 years and used them religiously to boost start the ISM450...zero issues.

Generator starters amp draw are minute compared to engine starters.  According to the specs for this replacement starter for that generator, Amazon.com: Lumix GC Electric Starter for Cummins Onan HomeSite Power 6500...  it pulls 1100 watts... that's less than 100amps.

You'll be fine with either pick IMHO.

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Lithium house battery generator starting

Reply #2 –
Thank you. That's what I needed to know.
Michael & Ginny
Frankfort, KY
1992 U240 GV Build #4116
2007 Mini Cooper

Re: Lithium house battery generator starting

Reply #3 –
I have two, 300and one 280 A/H Lipuls for house batteries. Yes a story there. Anyway these replaced three 210 A/H group 4D Lifeline AGMs. Part of the mis match story. Anyway I did this as a drop in using the original battery charging, boosting system. When cranking the engine with the boost engaged, I see about a 300-amp transfer to help crank the engine, even with the engine batteries able to do this one their own. So yes, boost is available.
This past weekend, I lived out of the motorhome for 3 days, parked in the lot at work for a project. Took two full days running the heat, microwave cooking, watching TV with surround sound. I brough the house battery bank down to 20% as indicated by the Victron meter. I put a popcorn bag in the microwave and turned it on. Battery meter showing near 180 amps, microwave, some lights, and the heat. Then went to start the generator. Crank a bit slow and started on the 3rd thump. ~440 A/H on the meter while cranking.
Anyway, batteries down to 20 SOC. Outside temp ~25F Microwave on, Generator started no problem. Lithium pack more then did the job? Resting voltage Lithium higher than AGM. Need some boost to help engine start, no problem. Limitation is still the wiring and boost system relay. I have 3000-watt inverter charger with 150-amp charge capacity. If I can get the genny started, I will be able to get the engine started.
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: Lithium house battery generator starting

Reply #4 –
I think the lithium manufacturers down-rate their max discharge amps mostly as a liability thing...they don't want them used exclusively as a start battery.  Also, the BMS is the limiting factor, and the rating is usually the max charge the BMS will provide, so the internal wiring is sized in proportion.  Short discharges (less than 5 seconds) will not make them explode.  Best bet is buy the biggest rated battery you can afford and check out the Will Prowse demolition video's on the Utoobs to see if a battery you are considering has met his ruthless review.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Lithium house battery generator starting

Reply #5 –
There are really 2 major issues with using Lithium batteries for starting batteries. The first of course is power delivery. The surge current needed to crank an engine requires much more robust wiring and the BMS within adding significantly to cost. The next is the temperature limitations especially for charging.  The chassis battery has to be available at any temp and as the engine is started ahs be able to take a charge from the alternator no matter what. The battery is a component that assists in voltage regulation and also the filter out the alternator noise and ripple. There are batteries marketed for engine starting marketed mostly for marine and other recreational equipment.
Starting RV generators is not that large of a load and there are inverters that can take even more power. If you get past the low temp limitation starting an RV generator eve Diesel at about 260 amps is no different than supply power for a 2,500-watt load on an inverter. Two batteries with 200-amp BMS get you there.
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: Lithium house battery generator starting

Reply #6 –
Thank you all for your input. All of your help was instrumental in my decision making process. I've ordered a 280ah LifePO4 battery this morning. The BMS manages to 210 max draw. I believe that will be sufficient for our lp generator starter. I'll let the forum know how it does.
Thank you again for your advice.

Michael
Michael & Ginny
Frankfort, KY
1992 U240 GV Build #4116
2007 Mini Cooper

Re: Lithium house battery generator starting

Reply #7 –
I know may be a little late.  Does this battery have Bluetooth and heaters when it gets cold?  Might check out Epoch batteries.  They have a us office and answer the phone during us days.  There are also 10% discount codes out there.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Lithium house battery generator starting

Reply #8 –
What I ordered doesn't have an internal heater but it does have a low/high temp cutoff and Bluetooth. We should begin to warm up here in central KY over the next few weeks (not that you would know it this week). That should give me until the fall to look at external heaters for the battery. Our coach is much older and requires a much lighter power load than many of the newer Foretravels, so I believe the single 280ah lifepo4 will be sufficient for our U240. It's certainly more available power than the 160ah Flooded lead acid it has currently.

Great resource though with Epoch. Thank you.
Michael & Ginny
Frankfort, KY
1992 U240 GV Build #4116
2007 Mini Cooper

Re: Lithium house battery generator starting

Reply #9 –
While still learning about Foretravel RVs, it seems that most have the house batteries in enclosed compartments, with only drain or vent openings in the bottom.  Seems to go with the use of AGM batteries. A surprise with mine is that the House battery box is actually in the middle of the basement, close to heater and inverter bays. As such with the heat on the battery compartment is always warm. Heat wasted warm. Even the storage compartments are kept warmer than I would have expected. I would do some experimenting and see how the battery box reacts to winter and if the box even needs additional heating to stay above freezing.  If you have the pipe vents in the bottom, test caps are available that can snap in place to close them. No need with the Lithium batteries.
Unless the planned use is to plug into park power heated batteries present some challenges charging off solar or generator supplies. Once the batteries are cold enough to "disable charging" power will be needed for hours to warm them up. In a closed compartment, it will take some time of below freezing weather for the batteries to get that cold. A small amount of heat from the furnace or however the tanks are heated maybe all that you need. It is 29F outside and my battery bay (49F) is warmer than the living room (43F) just from the Oasis heater being on. 
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: Lithium house battery generator starting

Reply #10 –
Same, if you're using the batteries and the coach, I've been in the single digits with no worries. My lithium's were reading low 40's

2000 GV320 4010 build #5712  2019-?
1999 Bounder 2000-2008
Bardstown, KY
🥃The Bourbon Capital of the World🥃

Re: Lithium house battery generator starting

Reply #11 –
We will see how it does. Until now, I wasn't concerned with the basement temperature. I wouldn't be surprised if we are using the coach, if that portion of the basement stays fairly warm. The other side of the battery compartment has the black and gray tanks as well.

I'm looking forward to feeling the advantage of the addition power while dry camping.
Michael & Ginny
Frankfort, KY
1992 U240 GV Build #4116
2007 Mini Cooper

Re: Lithium house battery generator starting

Reply #12 –
Michael, You need to set up your coach in your signature line. That way when you make a post everyone knows what coach you are talking about and you will not have to list what the coach is every time.  To do this  on the top right had side it says "My Account"  Once in your account you will see signature where you can add coach information and anything else you would like. When ever you make a post this information will show at the bottom.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago