Switch to Lithium without DC to DC or Li-BIM?

[Mocephus]

Hello friends! I am in the process of swapping out the FLA house batteries on our '05 Sig, with lithium. Our rig has the DD60 engine with the Leece-Neville 270 amp alternator, and the Xantrex RV3012 inverter/charger with the RC7-GS remote.

 

I have read that without adding a DC to DC charger or a Li-BIM, your alternator can be ruined from overheating. I have also heard that the high output 270 amp alternator can handle the charge to the lithium battery without issue.

 

Have any of you that have that same alternator, made a switch to Lithium without adding a DC to DC charger or a Li-BIM? If so, how long have you been running that setup (road hours)?

 

Thank you for your help!

 

Moe

[CMillet86]

I just did this on my 03 Dynasty. I purchased a DC-DC charger but haven’t installed it. I isolated the house batteries from the combiner. I run the generator most of the time when traveling and that charges the house battery. So that’s what I’m doing in the mean time. I rarely travel when it’s nice enough to not need the roof top a/c. I installed a 460 ah vaterrer battery. 

[Mocephus]

19 minutes ago, CMillet86 said:

I just did this on my 03 Dynasty. I purchased a DC-DC charger but haven’t installed it. I isolated the house batteries from the combiner. I run the generator most of the time when traveling and that charges the house battery. So that’s what I’m doing in the mean time. I rarely travel when it’s nice enough to not need the roof top a/c. I installed a 460 ah vaterrer battery. 

Thanks Cory. I looked at the Vatrer 460 too (it's a beast), but I'm leaning towards the Epoch because it is IP 54 rated against water and dust and my battery bays are somewhat exposed to both. If you don't mind, go ahead and hook the house batteries back up to the combiner and let me know if that smokes your alternator. 🙂

[Rocketman3]

I disconnected the alternator from the house batteries when I added lithiums (544ah) 3.5 years ago.  Didn’t want the issues on both ends… low batteries- high draws on alternator and possible overheating it and when traveling with full batteries - keeping the batteries at 14.4v for hours on end when driving.

Because we boondock a lot, I had already installed 800w of solar. Since then added another 420w when adding the residential fridge, and added an additional 300w over time (Starlink, etc).

Two years later I did add a Dc-Dc 30a charger and it’s nice but I use it less than I thought I would - when sun is out - don’t need it- if it’s been cloudy and I am driving- it helps but it is small. Since I added it, Victron has come out with a 50a Dc-Dc charger- kinda wish I had it… but the same two issues - either I don’t need it- or it’s still a bit small.

i put in a Victron Multiplus II 12/3000 2x120v inverter and the nice thing is - if my batteries are low - it can put lots of power into them in an hour. Every hours fills 20% of the battery. That’s the big advantage of Lithiums - Fast charging, no real absorbing charge, and they don’t mind not being charged 100% all the time.

One other factor- you need to plan a way to keep your chassis battery charged when not in use. I have ended up with an additional 100w panel and a small Victron mppt 75/15, that charges the chassis battery. (There are some small but constant loads on it - at least in my rig).

Good Luck!

[Mocephus]

1 hour ago, Rocketman3 said:

I disconnected the alternator from the house batteries when I added lithiums (544ah) 3.5 years ago.  Didn’t want the issues on both ends… low batteries- high draws on alternator and possible overheating it and when traveling with full batteries - keeping the batteries at 14.4v for hours on end when driving.

Because we boondock a lot, I had already installed 800w of solar. Since then added another 420w when adding the residential fridge, and added an additional 300w over time (Starlink, etc).

Two years later I did add a Dc-Dc 30a charger and it’s nice but I use it less than I thought I would - when sun is out - don’t need it- if it’s been cloudy and I am driving- it helps but it is small. Since I added it, Victron has come out with a 50a Dc-Dc charger- kinda wish I had it… but the same two issues - either I don’t need it- or it’s still a bit small.

i put in a Victron Multiplus II 12/3000 2x120v inverter and the nice thing is - if my batteries are low - it can put lots of power into them in an hour. Every hours fills 20% of the battery. That’s the big advantage of Lithiums - Fast charging, no real absorbing charge, and they don’t mind not being charged 100% all the time.

One other factor- you need to plan a way to keep your chassis battery charged when not in use. I have ended up with an additional 100w panel and a small Victron mppt 75/15, that charges the chassis battery. (There are some small but constant loads on it - at least in my rig).

Good Luck!

Thank you Michael! That's good information. We don't do a lot of boondocking and when not in use, our rig stays plugged in. My goal is to end up with about the same lithium AH ratings as I have with the FLA's that need replacing. Each new project related to our RV is definitely a learning experience with lots of research and advice from others, and this one is no exception. Thank you for helping me put the puzzle pieces together!

[timaz996]

I basically have the same set up as Michael, but I have 800 hours of lithium batteries and I use a 40 amp DC to DC charger by Renogy. I would recommend putting in a DC to DC charger. Just as a note I Boondock 95% of the time.

[Rocketman3]

If you have the BIRD (bi directional charging system - or something like that), and you disable the alternator charging the house bank - you have also disabled the inverter/charger (generator or shore) charging the chassis battery. If your unit has a small load on the chassis battery- you could find a dead chassis battery after a while. 
 

I choose to add a 100w solar panel to charge the chassis battery, others have added a small battery charger, so when on generator or shore the chassis is getting the charge it needs.

Also make sure you understand how the “Battery Boost” works on your rig for when/if you do need to boost the chassis battery. I believe it uses the BIRD system to pass that power. (I don’t have the BIRD system - so mine was a little more straightforward).

[hex_nut]

If your primary objective is to avoid maintenance issues and you do not do a lot of boondocking, I think you are going the wrong direction.  I have a coach basically the same vintage as yours.  I researched switching to lithium the last time I had to replace batteries.  I found that my inverter/charger cannot be made compatible with LifPo4 charging parameters (replacing it is quite expensive).  AND, as you have discussed, the requirement to separate the lithium batteries from the engine alternator.  All of that and the lithium batteries are still more expensive than lead acid.  So, my end result was to purchase 4 deep cycle AGM batteries for the house and 2 AGM starting batteries for my big CAT engine.  That was 2 years ago and I have been very happy with the results.  The AGM batteries are compatible with my inverter/charger and they are maintenance free.  I have not touched them since I installed them.  I would like to have the weight reduction of the lithium batteries and the fact that they recharge so much faster.  However, in my case it was just not practical.  Do lots of research before you go down that road.

Richard

      

[Mocephus]

1 hour ago, timaz996 said:

I basically have the same set up as Michael, but I have 800 hours of lithium batteries and I use a 40 amp DC to DC charger by Renogy. I would recommend putting in a DC to DC charger. Just as a note I Boondock 95% of the time.

Ok thank you Tim!

1 hour ago, Rocketman3 said:

If you have the BIRD (bi directional charging system - or something like that), and you disable the alternator charging the house bank - you have also disabled the inverter/charger (generator or shore) charging the chassis battery. If your unit has a small load on the chassis battery- you could find a dead chassis battery after a while. 
 

I choose to add a 100w solar panel to charge the chassis battery, others have added a small battery charger, so when on generator or shore the chassis is getting the charge it needs.

Also make sure you understand how the “Battery Boost” works on your rig for when/if you do need to boost the chassis battery. I believe it uses the BIRD system to pass that power. (I don’t have the BIRD system - so mine was a little more straightforward).

Thanks Michael, I’m trying to build the most simple system I can without adding electronics or disconnecting any functionality, so I had not intended on disabling the alternator from charging the house batteries.

I’ve also learned that I’d need a lot more batteries than I intend to purchase, in order to start the engine with the boost switch. So, I realize I’ll lose that function if I go to just one or two lithium batteries. 

[Mocephus]

1 hour ago, hex_nut said:

If your primary objective is to avoid maintenance issues and you do not do a lot of boondocking, I think you are going the wrong direction.  I have a coach basically the same vintage as yours.  I researched switching to lithium the last time I had to replace batteries.  I found that my inverter/charger cannot be made compatible with LifPo4 charging parameters (replacing it is quite expensive).  AND, as you have discussed, the requirement to separate the lithium batteries from the engine alternator.  All of that and the lithium batteries are still more expensive than lead acid.  So, my end result was to purchase 4 deep cycle AGM batteries for the house and 2 AGM starting batteries for my big CAT engine.  That was 2 years ago and I have been very happy with the results.  The AGM batteries are compatible with my inverter/charger and they are maintenance free.  I have not touched them since I installed them.  I would like to have the weight reduction of the lithium batteries and the fact that they recharge so much faster.  However, in my case it was just not practical.  Do lots of research before you go down that road.

Richard

      

Thanks Richard!  Yes I’ve been doing a lot of research and still learning. I haven’t ruled out AGM but want to have the flexibility to do more boondocking if we want. I also like the lithium benefits like 11 year warranty, longer life, shorter charge times, benefit of utilizing the full charge/ah rating vs just 50% for FLA and AGM, much less weight, zero maintenance, built in Bluetooth BMS, etc. I won’t need to buy a new inverter because the one I have will charge lithium to 80% which is the ideal storage charge for lithium. I will also keep the alternator on line to charge the house batteries, either with or without a dc to dc charger. 

Edited July 22 by Mocephus

[Tom Cherry]

38 minutes ago, Mocephus said:

Thanks Richard!  Yes I’ve been doing a lot of research and still learning. I haven’t ruled out AGM but want to have the flexibility to do more boondocking if we want. I also like the lithium benefits like 11 year warranty, longer life, shorter charge times, benefit of utilizing the full charge/ah rating vs just 50% for FLA and AGM, much less weight, zero maintenance, built in Bluetooth BMS, etc. I won’t need to buy a new inverter because the one I have will charge lithium to 80% which is the ideal storage charge for lithium. I will also keep the alternator on line to charge the house batteries, either with or without a dc to dc charger. 

All well and Good.  However, the odd’s of your inverter being “up to the job”, assuming a Magnum, being trustworthy and reliable are nil. If you talk to Magnum or at least the tech support folks a year ago, the average “end of life” for them is somewhere around 15 years.  YES, they last longer.  Mine is older. Many are. But we are seeing a higher failure rate in thepast year or so.  The remotes are also dying.  When they get flaky, they will, intermittently, change the parameters.  Been there - done that. I worked, for at least 6 months, with Magnum, almost monthly.  They were fascinated and also that I was willing to provide feedback.

They also said, on at least one ocassion, that the older models were not suited, nor recommended, for Lithiums.

YES…there are posts where individuals have done extensive and good work. In theory, if everything works and continues to work and one is very diligent in monitoring…it might work, with a new inverter and remote. 

Many of our electronics experts have speculated or hypothesized about converting to Lithiums.  They fully understand how Lithiums work and what is the best approach and using their Magnum inverters in any form, shape or fashion was a NO NO. They would install a new inverter, not a Magnum, which was designed specifically for and are field tested.

The 11 year warranty needs to be reviewed thoroughly as improper charging might be grounds for refusal.

One sent me this video and said it was fascinating and also one of the most informative as well as factual.  A big long…but before I would invest in Li as well as HOW to install…I’d watch this.  The testing and also practical experience is unbelievable….

Good Luck….

 

[Rikadoo]

Ya know its funney i been watching the new battery craze as they were dropped out on the market, an at 1st i thought they would be the hot set up, batteries, solar, dc to dc, new inverter. This all came about as my flooded batteries were rounding the corner of 5 years old. I finally had a hard discussion with myself… i realized im location drivin 80ish percent of the time, while the rest is somewhere between boondocking an storage, my flooded batteries work awsome when i do go “off road” however i had to come to grips with i really dont have a big footprint when im out there. An where i go its usually HOT so being a gearhead i like knowing i have my genny to handle the task at hand. No i will say i just had a customer bring his coach in for maint, he has the solar, the batteries, the converter an the “new inverter” that he has the system on 24/7. Even while in storage… hes a person whos job has him workingmore than he wants to and for him is happy knowing “if he wanted to” he could leave to go somewhere ANYTIME he wants!!! 
Dont get me wrong i get it, its not for me, but i get it. Im a person who is drivin by need, that if i NEED SOMETHING i will get it. Otherwise i will choose otherwise. 
Dont get me wrong, im not bashin anyone im just saying if you have a need get r done! However all the new tech is great but a person really needs to asses there individule needs, an just by keeping up on your flooded batteries COULD be enough for your needs.

[Mocephus]

49 minutes ago, Tom Cherry said:

All well and Good.  However, the odd’s of your inverter being “up to the job”, assuming a Magnum, being trustworthy and reliable are nil. If you talk to Magnum or at least the tech support folks a year ago, the average “end of life” for them is somewhere around 15 years.  YES, they last longer.  Mine is older. Many are. But we are seeing a higher failure rate in thepast year or so.  The remotes are also dying.  When they get flaky, they will, intermittently, change the parameters.  Been there - done that. I worked, for at least 6 months, with Magnum, almost monthly.  They were fascinated and also that I was willing to provide feedback.

They also said, on at least one ocassion, that the older models were not suited, nor recommended, for Lithiums.

YES…there are posts where individuals have done extensive and good work. In theory, if everything works and continues to work and one is very diligent in monitoring…it might work, with a new inverter and remote. 

Many of our electronics experts have speculated or hypothesized about converting to Lithiums.  They fully understand how Lithiums work and what is the best approach and using their Magnum inverters in any form, shape or fashion was a NO NO. They would install a new inverter, not a Magnum, which was designed specifically for and are field tested.

The 11 year warranty needs to be reviewed thoroughly as improper charging might be grounds for refusal.

One sent me this video and said it was fascinating and also one of the most informative as well as factual.  A big long…but before I would invest in Li as well as HOW to install…I’d watch this.  The testing and also practical experience is unbelievable….

Good Luck….

 

Thanks Tom. I have the Xantrex RV3012.

[timaz996]

If you really want to see the ins and outs of lithium batteries and what they can handle temperature wise look up a YouTube channel by Will Prowse

[Mocephus]

52 minutes ago, Rikadoo said:

Ya know its funney i been watching the new battery craze as they were dropped out on the market, an at 1st i thought they would be the hot set up, batteries, solar, dc to dc, new inverter. This all came about as my flooded batteries were rounding the corner of 5 years old. I finally had a hard discussion with myself… i realized im location drivin 80ish percent of the time, while the rest is somewhere between boondocking an storage, my flooded batteries work awsome when i do go “off road” however i had to come to grips with i really dont have a big footprint when im out there. An where i go its usually HOT so being a gearhead i like knowing i have my genny to handle the task at hand. No i will say i just had a customer bring his coach in for maint, he has the solar, the batteries, the converter an the “new inverter” that he has the system on 24/7. Even while in storage… hes a person whos job has him workingmore than he wants to and for him is happy knowing “if he wanted to” he could leave to go somewhere ANYTIME he wants!!! 
Dont get me wrong i get it, its not for me, but i get it. Im a person who is drivin by need, that if i NEED SOMETHING i will get it. Otherwise i will choose otherwise. 
Dont get me wrong, im not bashin anyone im just saying if you have a need get r done! However all the new tech is great but a person really needs to asses there individule needs, an just by keeping up on your flooded batteries COULD be enough for your needs.

Sage advice Rik. Thank you!

[Rocketman3]

One other point on Lithium batteries - you said the old inverter/charger is fine because it will only charge to 80% or so.  
 

yea that’s fine,  BUT you NEED one constant source to charge the battery (any battery) exactly how it wants and needs.

With Lithium batteries if you never fully charge them, then the BMS never has a chance to rebalance the cells.  After a while Lithium cells need rebalancing.  
 

If they never get rebalanced, over time the cells will get out of wack. In extreme cases, one cell will be low and one high… the low cell will cause the bms to shutoff much earlier than expected when discharging and the high cell will cause the bms to shutoff charging much earlier than expected.

For people I talk to about Lithium’s in RV’s there are 2 features that are extremely important to have in your batteries:

1. Low temp charging protection- it is easy to all of a sudden find yourself in a cold spell in the spring, fall, or winter.  This just protects the battery from getting destroyed if that happens.  
 

2. Some kind of way to check each cell voltage- Bluetooth is usually what they have, but you need some way to occasionally know your cells are in balance at the top of the charge cycle.  It can be by computer, Bluetooth app, screen, etc.  The way to fix an imbalance is to charge the battery and hold it at a level the bms will balance- while at the same time not so high it triggers a cell protection cutoff.  You need the cell voltage values to figure that out.

Yes I LOVE my Lithium’s, but I also realized there are several things that needs done to our rigs to make them work like they should and sometime the correct battery choice is AGM’s or Wet Cell Lead.

Good Luck

Edited July 22 by Rocketman3

[Mocephus]

5 minutes ago, timaz996 said:

If you really want to see the ins and outs of lithium batteries and what they can handle temperature wise look up a YouTube channel by Will Prowse

Thanks Tim. He's pretty good. Ive watched a few of his videos this weekend but it looks like I missed a couple related to lithiums so I'll check those out too!

[pwhittle]

How many amps have you guys seen being drawn from the alternator?

I have 2x230AH Lithium batteries and this morning the batteries were at 46%. I used my ML-ACR to join the chassis and house banks and measured 30 amp maximum charge to the batteries.

I suspect the cables and interconnects between the alternator and batteries are the limiting factor. I relocated the batteries to the same bay as the inverter, two bays forward of the drive axle. There is probably 40’ of +12v 4/0 cable and 10’ of 4/0 cable, plus 20’ of frame for the ground.

Not a significant load for our 2005 Signature with the 270 AH alternator.

Paul

[Mocephus]

1 hour ago, Rocketman3 said:

One other point on Lithium batteries - you said the old inverter/charger is fine because it will only charge to 80% or so.  
 

yea that’s fine,  BUT you NEED one constant source to charge the battery (any battery) exactly how it wants and needs.

With Lithium batteries if you never fully charge them, then the BMS never has a chance to rebalance the cells.  After a while Lithium cells need rebalancing.  
 

If they never get rebalanced, over time the cells will get out of wack. In extreme cases, one cell will be low and one high… the low cell will cause the bms to shutoff much earlier than expected when discharging and the high cell will cause the bms to shutoff charging much earlier than expected.

For people I talk to about Lithium’s in RV’s there are 2 features that are extremely important to have in your batteries:

1. Low temp charging protection- it is easy to all of a sudden find yourself in a cold spell in the spring, fall, or winter.  This just protects the battery from getting destroyed if that happens.  
 

2. Some kind of way to check each cell voltage- Bluetooth is usually what they have, but you need some way to occasionally know your cells are in balance at the top of the charge cycle.  It can be by computer, Bluetooth app, screen, etc.  The way to fix an imbalance is to charge the battery and hold it at a level the bms will balance- while at the same time not so high it triggers a cell protection cutoff.  You need the cell voltage values to figure that out.

Yes I LOVE my Lithium’s, but I also realized there are several things that needs done to our rigs to make them work like they should and sometime the correct battery choice is AGM’s or Wet Cell Lead.

Good Luck

Michael you are spot on. My plan is to, every few months,  bring the batteries up to 100% via a lithium battery charger. I'm looking at the Epoch 300ah battery that has the Bluetooth BMS features you describe and the active heating to guard against cold weather damage. It is also IP 54 rated against water and dust intrusion which I like since my battery bays are open somewhat to dust and water. The 11 year warranty is pretty sweet too.

[Tom Cherry]

9 hours ago, Mocephus said:

Thanks Tom. I have the Xantrex RV3012.

Thanks for the qualification. Monaco was still switching around or maybe the Bean Counters were controlling. I LIKE MAGNUM. I understand it. It is a TANK. BUT, I would NOT trust my 15 YO nor purchase a new one if I decided to go down that path.

BUT, I would also use the same LOGIC.  Would I TRUST the substantial investment in Li to a 20 year old inverter? NO for the obvious reasons I stated. I just got 25 years out of a GE Dishwasher that had an expected life span of 15. I knew what to fix or replace when it "gave me a signal" before it was terminal. I can go on about keeping computers and appliances and cars...LOL, running.  WAY past their normal life.

BUT, Li will NOT tolerate even a BOBBLE.  We have a resident in a town some 10 miles away. He took the "Lithium" battery out of his Tesla. YES, for a period of time...maybe still, Tesla used a MEMORY BATTERY.  It looked like a regular starting battery. Tesla got flack for using a wet cell or maybe even an AGM. So, they popped in a Lithium. It died. The owner watched a YouTube. Yanked it out.  Put it on the Granite counter top in is almost $1,000,000 residence.  Hooked up a 12/6 V 6/2 A charger....got a beer...watched a Saturday afternoon basketball game. 

Later BOOM.  Neighbor tried to extinguish it with a 2 3/4 #. FD arrived....they carted it out....in a blanket or whatever containment. Remodeling will be in excess of $100K.

I also have a buddy that has TORN APART a Mercedes Benz Hybrid Battery (his future SIL is the Service Manager at a MB dealer and they store the FAILED in the 2 rented PODS outback.). He constructed a "12 VDC" home emergency battery. He is like the guy in the VIDEO. A brilliant engineer with a curiosity...like tearing apart an old Radio Shack computer...just to see how it was made.

He is FULLY aware of all the cell balancing and such. He tested each "bank" or matrix and then matched them back up. He keeps it inside a container....

We, he used to be my boss, were the PTB for making decisions on new equipment or manufacturing systems vs MAKE DO or REPAIR. We had to include RELIABLITY as the criteria.  Like replacing a $50K "Press" rather than rebuilding as it was the Weak Link in a multimillion department....and that product line was our bread and butter with nice margins cash cow...

Good Luck....   

[CAT Stephen]

16 hours ago, Mocephus said:

Hello friends! I am in the process of swapping out the FLA house batteries on our '05 Sig, with lithium. Our rig has the DD60 engine with the Leece-Neville 270 amp alternator, and the Xantrex RV3012 inverter/charger with the RC7-GS remote.

 

I have read that without adding a DC to DC charger or a Li-BIM, your alternator can be ruined from overheating. I have also heard that the high output 270 amp alternator can handle the charge to the lithium battery without issue.

 

Have any of you that have that same alternator, made a switch to Lithium without adding a DC to DC charger or a Li-BIM? If so, how long have you been running that setup (road hours)?

 

Thank you for your help!

 

Moe

@Mocephus,

 

You will destroy the alternator as it is not designed for LiPO4 charging demand.  Also, Leaving LiPO4 in a discharged state (i.e below 80%) will reduce LiPO4 life and cycles, so avoid the out of band charging every few months.  The good news is that you can accomplish your goal, but it will be ~$1.1K for the new inverter / charger because your current inverter doesn't support LiPO4 plus ~$300 per 100Ah LiPO4 battery capacity.  Here are the steps:

- Remove any existing combiners and other hardware between the house and chassis electrical systems 

- Replace your current inverter / charge with a Victron Energy Multiplus 2, 3000VA: https://www.currentconnected.com/product/victron-12v-multiplus2-3000va/

- Buy & install an LiPO4 battery bank.  I recommend SOK from Current Connected:  https://www.currentconnected.com/product/sok-sk12v100-12v-solar-battery/

- (Optional) Purchase one of the following DC to DC chargers, install between your house and chassis electrical system: https://www.currentconnected.com/product/victron-orion-smart-tr-dc-dc-charger/

 

[RoadTripper2084]

16 minutes ago, CAT Stephen said:

Also, Leaving LiPO4 in a discharged state (i.e below 80%) will reduce LiPO4 life and cycles,

This isn't correct.  In fact, if you really want to optimize the lifespan/cycles for LiFePO4 batteries you store them at as close to 50% as possible. Of course, even worrying about the very mild loss of cycles on batteries that will support 5,000 to 10,000 cycles is not really worth the concern. The batteries will age out before you "wear" them out.  Old habits die hard though. 

I would agree that you can get by with your old non Lithium converter/charger but you should have at least one charge source that is Lithium aware so your batteries can occasionally be fully charged to 100% and allowed to effectively balance.  In my case I have an inexpensive Renogy 60A DC-DC charger for that purpose. Lots of folks use solar for the same.  Or you can spend the $ and upgrade your converter.

 

[Mocephus]

35 minutes ago, CAT Stephen said:

@Mocephus,

 

You will destroy the alternator as it is not designed for LiPO4 charging demand.  Also, Leaving LiPO4 in a discharged state (i.e below 80%) will reduce LiPO4 life and cycles, so avoid the out of band charging every few months.  The good news is that you can accomplish your goal, but it will be ~$1.1K for the new inverter / charger because your current inverter doesn't support LiPO4 plus ~$300 per 100Ah LiPO4 battery capacity.  Here are the steps:

- Remove any existing combiners and other hardware between the house and chassis electrical systems 

- Replace your current inverter / charge with a Victron Energy Multiplus 2, 3000VA: https://www.currentconnected.com/product/victron-12v-multiplus2-3000va/

- Buy & install an LiPO4 battery bank.  I recommend SOK from Current Connected:  https://www.currentconnected.com/product/sok-sk12v100-12v-solar-battery/

- (Optional) Purchase one of the following DC to DC chargers, install between your house and chassis electrical system: https://www.currentconnected.com/product/victron-orion-smart-tr-dc-dc-charger/

 

Thank you Stephen for your advice and the excellent links. If I decide to go that route the links will be very helpful! 

17 minutes ago, RoadTripper2084 said:

This isn't correct.  In fact, if you really want to optimize the lifespan/cycles for LiFePO4 batteries you store them at as close to 50% as possible. Of course, even worrying about the very mild loss of cycles on batteries that will support 5,000 to 10,000 cycles is not really worth the concern. The batteries will age out before you "wear" them out.  Old habits die hard though. 

I would agree that you can get by with your old non Lithium converter/charger but you should have at least one charge source that is Lithium aware so your batteries can occasionally be fully charged to 100% and allowed to effectively balance.  In my case I have an inexpensive Renogy 60A DC-DC charger for that purpose. Lots of folks use solar for the same.  Or you can spend the $ and upgrade your converter.

 

Thank you Ken. That’s what I’m thinking too. A lithium charger should solve the problem of periodically balancing the cells. 

[Mocephus]

3 hours ago, Tom Cherry said:

Thanks for the qualification. Monaco was still switching around or maybe the Bean Counters were controlling. I LIKE MAGNUM. I understand it. It is a TANK. BUT, I would NOT trust my 15 YO nor purchase a new one if I decided to go down that path.

BUT, I would also use the same LOGIC.  Would I TRUST the substantial investment in Li to a 20 year old inverter? NO for the obvious reasons I stated. I just got 25 years out of a GE Dishwasher that had an expected life span of 15. I knew what to fix or replace when it "gave me a signal" before it was terminal. I can go on about keeping computers and appliances and cars...LOL, running.  WAY past their normal life.

BUT, Li will NOT tolerate even a BOBBLE.  We have a resident in a town some 10 miles away. He took the "Lithium" battery out of his Tesla. YES, for a period of time...maybe still, Tesla used a MEMORY BATTERY.  It looked like a regular starting battery. Tesla got flack for using a wet cell or maybe even an AGM. So, they popped in a Lithium. It died. The owner watched a YouTube. Yanked it out.  Put it on the Granite counter top in is almost $1,000,000 residence.  Hooked up a 12/6 V 6/2 A charger....got a beer...watched a Saturday afternoon basketball game. 

Later BOOM.  Neighbor tried to extinguish it with a 2 3/4 #. FD arrived....they carted it out....in a blanket or whatever containment. Remodeling will be in excess of $100K.

I also have a buddy that has TORN APART a Mercedes Benz Hybrid Battery (his future SIL is the Service Manager at a MB dealer and they store the FAILED in the 2 rented PODS outback.). He constructed a "12 VDC" home emergency battery. He is like the guy in the VIDEO. A brilliant engineer with a curiosity...like tearing apart an old Radio Shack computer...just to see how it was made.

He is FULLY aware of all the cell balancing and such. He tested each "bank" or matrix and then matched them back up. He keeps it inside a container....

We, he used to be my boss, were the PTB for making decisions on new equipment or manufacturing systems vs MAKE DO or REPAIR. We had to include RELIABLITY as the criteria.  Like replacing a $50K "Press" rather than rebuilding as it was the Weak Link in a multimillion department....and that product line was our bread and butter with nice margins cash cow...

Good Luck....   

Thank you Tom!

[Paul J A]

15 hours ago, Mocephus said:

Ok thank you Tim!

Thanks Michael, I’m trying to build the most simple system I can without adding electronics or disconnecting any functionality, so I had not intended on disabling the alternator from charging the house batteries.

I’ve also learned that I’d need a lot more batteries than I intend to purchase, in order to start the engine with the boost switch. So, I realize I’ll lose that function if I go to just one or two lithium batteries. 

Moe; I think you would be much happier and less expense with AGM .  

Edited July 22 by Paul J A
clarify