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

[Mocephus]

5 minutes ago, Paul J A said:

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

Thanks Paul!

[Tom Cherry]

18 minutes ago, Paul J A said:

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

Many of would, agree....if the premise was going from an inverter that would work well on AGM and keeping it set up properly and being aware of any issues....as compared to the complexity (and the lack of simplicity) of Lithiums.

Totally AGREE from TWO Points of VIEW.

The potential cost of destroying or damaging the Lithiums is great.  Sort of like in the Stock Market.  You have to weigh you RISK vs REWARD tolerance.  Steady investing such as buying an S&P 500 Index fund will pay off and all the CFP and CFA will say that.  

BUT, if you don't have the patience or the resources and you need MORE gains...you pick the equities that you think will outperform the market.  You invest in them....knowing that if you make the wrong choice, you might lose all you capital or the money that you put in them.  

I consider using 2005 Technology equipment to maintain, or maybe NOT TO HARM, Lithium batteries as High Risk...High Reward.  

SO, if your inverter goes south or there is a loose connection or any of the pitfalls that we deal with here....DAILY....and many  of us focus on these....then the AGM's are safer and easier and less risky.

BUT, I will say that there is also a roaring debate as to Buggy Whip vs say a Model T...  as in Traditional FLA batteries vs AGM's.  We have many topics that said... 

My AGM's only lasted 3 years.  I got WAY longer life from the OEM batteries.  I switched from FLA because I got tired or watering them and doing maintenance  I had read that the AGM's were just PLUG and PLAY and you didn't have to do any maintenance.  WHAT HAPPENED...

The answer, after all the trouble shooting and the tedious reconstruction of the Crime Scene (OD'ed on NCIS...LOL).  The batteries were of reasonable quality. But, there was an issue in the BIRD ( TWO WAY CHARGING) system.  There was a mistake made in reprogramming the Inverter.  There was an issue such as a connection or cable failure.  Someone NEVER told the member that they should NOT routinely EQUALIZE the AGM's.  Bottom line, the AGM's were OVERCHARGED.  Here is the simplistic CULPRIT..  When you mess up and let the electrolyte drop into the plates, hopefully, you catch it and replenish it.  BUT, you can SEE inside.  That comes from some or a combination of the "causes"
 

NOW...you can NOT see inside the AGM, so you can NOT replenish the electrolyte.  The AGM is made to be be cycled and recharged...but NEVER OVERCHARGED...or Equalized.  When you do that...you BOIL OFF the water (distilled) and the electrolyte drops.  The Plates are dry and exposed.  The Lead Oxide on the plates in an FLA or an AGM is "typically" the same. When there is exposed area at the TOP of the plates....then the Lead Oxide flakes off. The PLATES are NOT PURE LEAD....

SO, that flaking gets worse. Then the residue or flakes or slivers collects in the bottom of the cells....and when it gets HIGH enough....then the BOTTOM of the Cell shorts out to the bottom of the plate.  THUS, the cell is dead.  We know that because the battery reads 4.X VDC....so it is TOAST....NOTHING can be done.

The OTHER issue, with the AGM, is that if the electrolyte gets low or is being boiled off, then the cells will lose the surface area.  NOT SHORTED OUT...but they will NOT recharge. The electrolyte in a FLA can be replenished and the Specific Gravity can be tested.  I have run MATCHED batteries that I knew had GOOD cells and GOOD voltage and only used TWO as in one bank.

Bottom LINE...AGM is sometimes "MISREPRESENTED" as the DON'T TOUCH ME solution.  YES, in theory the AGM's do NOT require cell maintenance.  BUT, what sometimes is NEVER SAID.  The FLA and the AGM, if they sit for 6 months of so....BOTH need to BE CYCLED or Discharged or Drained to around 50% and then recharged.  That replenished or causes the Electrolyte to be more homogenous and the batteries will then recharge to PEAK or 100% SOC.

SO...IF you go to AGM...then remember.  They STILL have to treated, unless one BOONDOCKS regularly, just like a FLA.

There is ALSO more risk, as in higher cost, of replacing the AGM compared to FLA..

The CONCLUSION....Keep READING.  Keep ANALYZING.  Then, as time goes on, the correct battery type and configuration will be obvious. I was asked to put this together for any member that wanted a comprehensive PRIMER on batteries in general. It pertains to AGM as well as FLA...

 

[Mocephus]

26 minutes ago, Tom Cherry said:

Many of would, agree....if the premise was going from an inverter that would work well on AGM and keeping it set up properly and being aware of any issues....as compared to the complexity (and the lack of simplicity) of Lithiums.

Totally AGREE from TWO Points of VIEW.

The potential cost of destroying or damaging the Lithiums is great.  Sort of like in the Stock Market.  You have to weigh you RISK vs REWARD tolerance.  Steady investing such as buying an S&P 500 Index fund will pay off and all the CFP and CFA will say that.  

BUT, if you don't have the patience or the resources and you need MORE gains...you pick the equities that you think will outperform the market.  You invest in them....knowing that if you make the wrong choice, you might lose all you capital or the money that you put in them.  

I consider using 2005 Technology equipment to maintain, or maybe NOT TO HARM, Lithium batteries as High Risk...High Reward.  

SO, if your inverter goes south or there is a loose connection or any of the pitfalls that we deal with here....DAILY....and many  of us focus on these....then the AGM's are safer and easier and less risky.

BUT, I will say that there is also a roaring debate as to Buggy Whip vs say a Model T...  as in Traditional FLA batteries vs AGM's.  We have many topics that said... 

My AGM's only lasted 3 years.  I got WAY longer life from the OEM batteries.  I switched from FLA because I got tired or watering them and doing maintenance  I had read that the AGM's were just PLUG and PLAY and you didn't have to do any maintenance.  WHAT HAPPENED...

The answer, after all the trouble shooting and the tedious reconstruction of the Crime Scene (OD'ed on NCIS...LOL).  The batteries were of reasonable quality. But, there was an issue in the BIRD ( TWO WAY CHARGING) system.  There was a mistake made in reprogramming the Inverter.  There was an issue such as a connection or cable failure.  Someone NEVER told the member that they should NOT routinely EQUALIZE the AGM's.  Bottom line, the AGM's were OVERCHARGED.  Here is the simplistic CULPRIT..  When you mess up and let the electrolyte drop into the plates, hopefully, you catch it and replenish it.  BUT, you can SEE inside.  That comes from some or a combination of the "causes"
 

NOW...you can NOT see inside the AGM, so you can NOT replenish the electrolyte.  The AGM is made to be be cycled and recharged...but NEVER OVERCHARGED...or Equalized.  When you do that...you BOIL OFF the water (distilled) and the electrolyte drops.  The Plates are dry and exposed.  The Lead Oxide on the plates in an FLA or an AGM is "typically" the same. When there is exposed area at the TOP of the plates....then the Lead Oxide flakes off. The PLATES are NOT PURE LEAD....

SO, that flaking gets worse. Then the residue or flakes or slivers collects in the bottom of the cells....and when it gets HIGH enough....then the BOTTOM of the Cell shorts out to the bottom of the plate.  THUS, the cell is dead.  We know that because the battery reads 4.X VDC....so it is TOAST....NOTHING can be done.

The OTHER issue, with the AGM, is that if the electrolyte gets low or is being boiled off, then the cells will lose the surface area.  NOT SHORTED OUT...but they will NOT recharge. The electrolyte in a FLA can be replenished and the Specific Gravity can be tested.  I have run MATCHED batteries that I knew had GOOD cells and GOOD voltage and only used TWO as in one bank.

Bottom LINE...AGM is sometimes "MISREPRESENTED" as the DON'T TOUCH ME solution.  YES, in theory the AGM's do NOT require cell maintenance.  BUT, what sometimes is NEVER SAID.  The FLA and the AGM, if they sit for 6 months of so....BOTH need to BE CYCLED or Discharged or Drained to around 50% and then recharged.  That replenished or causes the Electrolyte to be more homogenous and the batteries will then recharge to PEAK or 100% SOC.

SO...IF you go to AGM...then remember.  They STILL have to treated, unless one BOONDOCKS regularly, just like a FLA.

There is ALSO more risk, as in higher cost, of replacing the AGM compared to FLA..

The CONCLUSION....Keep READING.  Keep ANALYZING.  Then, as time goes on, the correct battery type and configuration will be obvious. I was asked to put this together for any member that wanted a comprehensive PRIMER on batteries in general. It pertains to AGM as well as FLA...

 

Thank you again Tom. Good insight!

[pwhittle]

6 hours 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/

 

Based on my personal experience, admittedly not very long yet, I strongly disagree with everything in this post.

No disrespect intended. This is the common thinking that is published repeatedly, but I have not been able to personally substantiate most of the above claims.

Some other details of my coach that are non-standard and different from Moe's).

1 I previously upgraded to a Magnum MS2812 Inverter because I wanted Pure Sine Wave so the Microwave would work correctly on the inverter. When stored with shore power available, I set the absorb and float to 13.3V. The batteries stay at just under 80% charged. When I am travelling and expect to need to use the batteries overnight, I set the Absorb to 14.4V and the float to 13.6V. 

2 I went from 600AH Lifeline AGM to 460 AH Lithium (2x230AH, each with a 200A BMS), and relocated them in the same bay as the inverter.

3 I installed an ML-ACR in place of the Big Boy and BCC. The Big Boy/BCC is not one of Intellitec's finest designs. The ML-ACR operates as expected, and has a lifetime warranty.

Edited July 22 by pwhittle

[vito.a]

I know of several Monaco Signature and Country Coach Magnum/Affinity owners that have installed lithium battery banks with the OEM Leece Neville 270-amp alternator connected.  So far there are no issues.  These big alternators are very different than standard automobile alternators.    

You need the recommended charging profile from your battery manufacturer.  Then talk to the inverter technicians.  You will need someone that understands batteries and is not just quoting from a cheat sheet.  I used to speak to Glenn at Magnum, but he has since retired.  

Good luck!

[pwhittle]

Update on alternator charging loads with Lithium.

On this trip I was able to make measurements with different SOC’s of the battery bank.

When I had the Lithium bank at 21%, I did see a peak of 56A into the battery bank, but it quickly dropped (within minutes) to 40A.

Paul

[Mocephus]

11 hours ago, vito.a said:

I know of several Monaco Signature and Country Coach Magnum/Affinity owners that have installed lithium battery banks with the OEM Leece Neville 270-amp alternator connected.  So far there are no issues.  These big alternators are very different than standard automobile alternators.    

You need the recommended charging profile from your battery manufacturer.  Then talk to the inverter technicians.  You will need someone that understands batteries and is not just quoting from a cheat sheet.  I used to speak to Glenn at Magnum, but he has since retired.  

Good luck!

Thank you Vito! I’ll definitely do that!

[Ivylog]

I put a remote temp sensor on my alternator when I put in 600AH of Lithiums… alternator did not overheat mainly because it was only putting out 75 amps. Disconnected the solar and various SOC (as low as 20%) made no difference… always 60-80 amps.

I’d already installed a cutoff switch on a small green wire on the BigBoy to disconnect it when dry camping… a cheaper solution instead of a dc-dc IF your alternator puts out too many amps. I’ll let you decide how many is to many.

[Mocephus]

On 7/31/2024 at 11:50 AM, Ivylog said:

I put a remote temp sensor on my alternator when I put in 600AH of Lithiums… alternator did not overheat mainly because it was only putting out 75 amps. Disconnected the solar and various SOC (as low as 20%) made no difference… always 60-80 amps.

I’d already installed a cutoff switch on a small green wire on the BigBoy to disconnect it when dry camping… a cheaper solution instead of a dc-dc IF your alternator puts out too many amps. I’ll let you decide how many is to many.

Thank you Dick! 

[RoadTripper2084]

I just want to point out that you can pick up a decent DC-DC charger for $169 on amazon (40A), or $210 for the 60A version.

Renogy 12V 40A DC to DC On-Board Multi-stage Battery Charger

I've been using the 60A version without issues for almost 3 years.  I just don't understand all the hacks/workarounds being pursued when a proper solution is perfectly affordable.  

[Mocephus]

On 8/6/2024 at 11:51 AM, RoadTripper2084 said:

I just want to point out that you can pick up a decent DC-DC charger for $169 on amazon (40A), or $210 for the 60A version.

I've been using the 60A version without issues for almost 3 years.  I just don't understand all the hacks/workarounds being pursued when a proper solution is perfectly affordable.  

Thank you Ken. I haven’t completely ruled out the DC to DC charger route so thank you for the link!

[Ivylog]

5 hours ago, RoadTripper2084 said:

 I just don't understand all the hacks/workarounds being pursued when a proper solution is perfectly affordable.  

I’d be curious if you bypassed your DC-DC, how many amps it would charge. I wasn’t entirely surprised mine doesn’t overcharge…didn’t with 800AH of AGMs. $200 saved is actually $300 I don’t have to earn.

[cbr046]

I'm curious how many amps a TYPICAL stock coach alternator puts out with a fresh start, lights on, AC fan on max and, of course, all the engine and transmission circuits . . . . basically everything the alternator MIGHT put out before charging the coach batteries. 

Every model & chassis will be different, but it might give a WAG as to how big of a DC-DC charger (for coach side) might be possible.

Or if someone has taken actual measurements . . . .

- bob

[RoadTripper2084]

19 hours ago, Ivylog said:

I’d be curious if you bypassed your DC-DC, how many amps it would charge. I wasn’t entirely surprised mine doesn’t overcharge…didn’t with 800AH of AGMs. $200 saved is actually $300 I don’t have to earn.

Yeah, that was my original plan, to not install the DC-DC initially and measure the load. But then I found this unit on sale at the time and just picked it up. It also simplified my wiring changes since I could just rip out the old battery isolator, chassis battery maintainer, and the "big boy" boost solenoid which conveniently left enough room for the DC-DC charger in my rear engine bay electrical box.  

[Grey Goose]

On 7/22/2024 at 7:57 AM, 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....   

Tom, 

I really do appreciate all your input and dedication to this forum but when you tell the story about the fire and Lithium batteries I think you really should differentiate between Lithium ION (Tesla) and Lithium Iron Phosphate battery chemistry.  This is an important distinction as most users on this forum are considering LIFPO4 (Lithium Iron Phosphate) which is a very stable and safe chemistry that likely has no more risk to fire than a FLA regardless of what charger is being used. 

[Mocephus]

UPDATE: After much research and consultation with others, I elected to make the switch to lithium without purchasing a new "lithium compatible" inverter, or a new "lithium compatible" solar charge controller or a DC to DC charger. I simply removed the 8 FLA batteries and cables, cleaned and repainted the battery trays, changed the charge profiles on my inverter and solar charge controller...and hooked up the new EPOCH 300AH lithium house battery.

Here's how it all came together:

I started with 8 - 6v Trojan batteries rated at 225AH for a total of 900AHs (12v). Because you can only discharge FLAs and AGMs to 50% SOC, the effective AH rating of the Trojans is actually 450AH.

My inverter (Xantrex RV3012)  does not have a custom charge profile feature. It only has settings for FLA, AGM and GEL batteries. The charge profile for GEL batteries shows a BULK VDC of 14.1, ABSORB of 14.1 and FLOAT of 13.6. That setting also does not do an equalizing charge (which would damage a lithium battery).

I called EPOCH and gave them the charging profile for the GEL setting on my inverter and the technician assured me that it would be fine to use that profile and that it would not damage the battery. He did say that there was a chance the inverter may not charge the battery to 100%.

Following a forum member's advice, I changed my solar charge controller to its AGM setting which also charges in the same range as the Xantrax inverter's GEL setting, and also does not perform an equalization charge when set to AGM.

Starting at a 50% SOC, I installed the battery and let it charge overnight while plugged into shore power. The next morning the battery was charged to 98%.

There had been a fair amount of concern that I would burn up my alternator if I did not install a DC to DC charger, so I tested it out. I first drained the lithium down to 13%. Then I cranked the engine and let it run at high idle for over half an hour while monitoring the charge going into the battery. The highest it ever got was 32A. The Neece-Leville alternator on our rig is rated at 270A. The battery has a max charge rating of 200A.

So, I'm going to see how the battery performs under the above scenario. If all goes well, here's what I see as the pros and cons:

PROS

- No more dealing with the hassle of maintaining water levels in the FLA batteries, or the recommended "exercising" of AGMs, if I had gone that route.

- No more concerns about corrosion and rust caused by the off-gassing of the FLAs.

- Went from 12 cable connections (and the requisite maintenance of those) to 2 cables.

- Reduced the weight of the house batteries by 438 lbs.

- Gained an extra storage bay tray that once housed 4 of the FLAs.

- Max 80% (recommended) use of the AH rating as opposed to FLA and AGM, of which only 50% is useable.

- Constant voltage output throughout the discharge cycle.

- Longer lifespan (11 year warranty)

- Faster charging times

- Lower cost over the life of the battery

CONS

- Sacrificed approximately 210 AHs by going to just one 300 AH lithium battery....assuming an 80% max discharge for the lithium (300ah *.8 = 240 effective AH vs 450 for the FLAs). If I need more, I can easily add up to three additional lithiums.

- Up-front Cost: If I had added a second battery to get closer (apples to apples) to the 450 effective AH rating of the FLAs, my cost would have been approximately $657 higher than replacing all 8 FLAs. By adding just the one battery, my cost was actually $355 less.

- Lost the ability to use the battery boost feature in case the chassis batteries became weak. The Lithium battery does not have the cranking amps required to start the engine and attempting to do so could damage the battery. I could, however, use the battery boost switch to charge the chassis batteries from the house batteries....or carry jumper cables.

I'll be watching the battery's performance and I'll do an update if any issues arise but please let me know if you see something that I'm missing!

[Benjamin]

Why only 32A from the alternator?  I'd double check the voltages under load, shouldn't that be quite a bit higher?  I thought the biggest advantage of Li was the fast charge rate, that's not a fast charge rate. 300ah of lead would take more amps than that.  Part of the danger to the alternator is overloading with total amps and overheating, Li performs different than lead.  Lead you can charge with constant voltage and the current tapers off as the battery gets full.  Li doesn't do that, it can continue to take large current at normal voltage, that's why they're charged with current control.  When the BMS says the battery is too full, it will disconnect the battery, that is not good to do to an alternator putting out full power, that "load dump" is the other danger to the alternator.

Also, anybody hooking up batteries parallel should recognize the wiring issue with your old trojans, they should be balanced with one cable on each parallel string for best life.

Edited August 13 by Benjamin

[Mocephus]

44 minutes ago, Benjamin said:

Why only 32A from the alternator?  I'd double check the voltages under load, shouldn't that be quite a bit higher?  I thought the biggest advantage of Li was the fast charge rate, that's not a fast charge rate. 300ah of lead would take more amps than that.  Part of the danger to the alternator is overloading with total amps and overheating, Li performs different than lead.  Lead you can charge with constant voltage and the current tapers off as the battery gets full.  Li doesn't do that, it can continue to take large current at normal voltage, that's why they're charged with current control.  When the BMS says the battery is too full, it will disconnect the battery, that is not good to do to an alternator putting out full power, that "load dump" is the other danger to the alternator.

Also, anybody hooking up batteries parallel should recognize the wiring issue with your old trojans, they should be balanced with one cable on each parallel string for best life.

Thanks Benjamin. I can’t explain why only 32A from the alternator. Another member posted in this string that he did a similar test and saw his averaging around 40A with a short bump to 50A. I have been watching the charging cycle when on shore power and have seen the inverter reduce the current as the SOC increased.

My understanding is the alternator does not put out full power unless there is a demand for full power, otherwise it only puts out what is needed, so hopefully there would not be an instance of the BMS shutting off while the alternator is pumping out 270 AMPS.

During my test, I did turn the headlights on to give it some load. I have ordered a ac/dc current clamp multimeter. I’ll use it to measure the alternator’s total output during another test.

Regarding the wiring of the FLAs, I’m assuming that was done at the factory as it does match my wiring diagrams.

Thanks for your insight, I’m admittedly learning as I go!

Moe

[Ivylog]

Lots of BS from the “Experts”. I’ve posted for 2 years you don’t need a new inverter charger as the AGM (and now Gell from ^^^^) will charge Lithiums. IF you think you need a Lithium profile, the newer RC-50L ($200) display will do that. My recommendation is instead of spending $200 on a L display, spend it on an additional 100A charger and turn the 3 stage charging feature off, set the voltage at 14.6 and power off the block heater outlet. This will decrease your generator run time 40-50%.

I can’t explain why my alternator only charges my 600+AH of Lithiums 60-70 amps regardless of the SOC. Again, so much for the Experts.

[Mocephus]

31 minutes ago, Ivylog said:

Lots of BS from the “Experts”. I’ve posted for 2 years you don’t need a new inverter charger as the AGM (and now Gell from ^^^^) will charge Lithiums. IF you think you need a Lithium profile, the newer RC-50L ($200) display will do that. My recommendation is instead of spending $200 on a L display, spend it on an additional 100A charger and turn the 3 stage charging feature off, set the voltage at 14.6 and power off the block heater outlet. This will decrease your generator run time 40-50%.

I can’t explain why my alternator only charges my 600+AH of Lithiums 60-70 amps regardless of the SOC. Again, so much for the Experts.

Thank you Dick. That sounds like a beast of a charger! I’ll check that out for sure!

[Tom Cherry]

On 8/7/2024 at 1:02 PM, Grey Goose said:

Tom, 

I really do appreciate all your input and dedication to this forum but when you tell the story about the fire and Lithium batteries I think you really should differentiate between Lithium ION (Tesla) and Lithium Iron Phosphate battery chemistry.  This is an important distinction as most users on this forum are considering LIFPO4 (Lithium Iron Phosphate) which is a very stable and safe chemistry that likely has no more risk to fire than a FLA regardless of what charger is being used. 

Coincidentally, I was doing my EXERCISE of my Trojans yesterday and some interesting...seemingly strange things occurred.  I did some further experiments and then talked to two other members who have electronics backgrounds and we have theorized a few things....which explains why we are seeing the recent high failure rates of the Magnum inverters.  AGAIN...I like Magnum and I have spent time from the first year I owned (purchased new) it in 2009 and then as a moderator started helping folks in 2010 or 11 and also noting why we are seeing the uptick in failures.  OLD AGE...

I ran my batteries down to about 60% SOC the first time.  All was well.  Then I put the MH back in the normal state and left it to recharge overnight. Sometime in the middle of the recharge a fault occurred.  I know that as the Microwave and refrigerator and coffee maker snitched. The power was off.  It was NOT the 50A service.  I have had the MH in storage for a long time and left if for several days as I put it back in covered storage when Debby passed on NC.

Then I ran down the batteries even more yesterday. I won't delve in to what I also confirmed about the Low Battery Cut Off setting and I will be updating the Battery 101 and Magnum setup files. That in itself is a separate topic....but the load or the spikes of your load will dictate exactly WHERE and WHY the LBCO should be set lower than most folks "THINK"...and this has been confirmed by Magnum.

OK....during the recharging yesterday, same thing.  Lost power internally...as he LED's were flashing.  The Magnum Remote was in a ERROR STATE. The inverter was overheating.  When that happens, the charging as well as the pass through 120 VAC to the GFCI and the Refrigerator and the MIcrowave shuts down. The Inverter will restart after the FET's cool oll.

The settings were the same as I had been using all the years.  BUT, in a confession, I had left the MH in storage and we did not travel.  SO, this is all catch.

WHY DID THE FET's OVERHEAT?  This has NOT occurred before...  The charging rate was set to 80% which is 10% LOWER than Magnum recommends....FOR A NEW UNIT. 

After talking to the other two members....one theorized....and has had experience with this phenomenon when he repaired mother boards for a PC as well as general knowledge. There are two BANKS, if you will, in the Magnum.  On the PCB, there are FET's.  These are the HEART of the Magnum.  If you go into the Technical function of the remote there are several ways of checking on the Magnum and Magnum tech support usually has you scroll through and read back the information.

The Magnum has two cooling fans and two sensors.  One for each bank of FET's.  My FET's were NOW OVERHEATING.  They had never done this before and I had exercised and recharged the batteries many times....like one should do.

The RATIONALE...  The Magnums and the MH's we have here are getting older. As I have stated, we have had MORE total Magnum failures requiring a new inverter in the past two years than during the prior 3 or 4 years...since we set up the new site.  WHY?  SIMPLE.

When the FET's are mounted on the PCB or the MAIN BOARD, there is an array of heat sinks or maybe one massive one.  Matters NOT.  The heatsink is on the board and the FET is mounted on top of it...The heat sink is to dissipate HEAT...the CAUSE of MOST FAILURES.  Every PC or electronic system with a large processing chip or FET's whatever have a HEAT Sink and a Fan. All desktop has such. Over the years if you have ever gone inside, you may find a separate fan and coiling system for the main chip.  NOW, in the Magnum, the FET's are "BEDDED" or there is a layer of Thermal Conductive Heat Sink Compound.  Some call it PASTE....some GREASE.  It is used to provide HEAT TRANSFER from the FET body to the HEAT Sink. It ENHANCES or is there for 100% HEAT transfer from the FET to the Heat Sink. Then there is a sensor and a cooling fan. Thermal Conductive Heat Sink Compound is NOT A 100% GOOD until Gabriel blows the Trumpet. It eventually deteriorates or breaks down and starts to crystalize.  Therefore, it is losing it's ability to TRANSFER the FET heat to the heat SINK.  COMMON PROBLEM.  Many folks have tools to remove the FET and then clean and replace the Heat Sink Compound.  BUT, if the FET is damaged or one does not catch that in time.  BINGO...a DEAD FET.

That is what happened to me and what is going on inside it. This is NOT something new and revolutionary.  Magnum suggests allowing cooling or air circulation where the Inverter is located. Many of our old timers have, occassionally experienced this and we open the bays or some put a small fan down there during times of high temps.

SO...my comments about the AGING of the Magnums now is a valid conclusion.  

SO...back to the gist of the comments. Magnum told me....  Lithiums AIN'T our Thing.  OK..  BUT, if one decides or has experimented and they have an older Magnum and it seems to charge their banks OK.  FINE.  BUT, my experience ALSO tells me that the Remotes are MORE vulnerable.  I would PERSONALLY purchase a NEW REMOTE...on GENERAL principles...as the Remotes change the setup parameterss... DRASTICALLY.  Magnum says that.  I know that....mine failed.

THEN...my point is.  If there is a known failure of one component...the REMOTE...and then if there is the AGING factor or the breakdown of the Thermal Heat Sink Paste and the Inverter is running HOTTER....why would you want to risk destroying the Li Bank?

The SOLUTION...as most will say... CUT BACK ON THE CHARGE RATE.  I will now throttle mine back to 50%. I KNOW it worked fine in the past at 80. SO for inverters older than the 15 or so years...I am recommending cutting it back and will update the files.

That's my logic.  One of the members that I talked to yesterday has 10 YO Trojans and they will still, after exercising, go back to 100 SOC.  His inverter is 17 Years old. He know how to convert to Lithiums and had researched and watched videos and also commented here. His "PLAN"...subject to change...WHEN (NOT IF) his Magnum fails, he will probably NOT replace it.  He will do the upgrade to Lithiums with a Victron and also the other required MOD's...which have been posted in all the topics and are working today. 

That's my point. I am NOT anti-Lithium.  I an AITI-WASTING money or gambling on 15 - 20 year old electronics that have TWO KNOWN Failures....  And the failures COULD, as well as WILL destroy the Lithiums.  We have had at least 20 odd occasions of just "Popped in Lithiums" and did very little or maybe was told NOT to make any changes.  Three to five YEARS is when the fail...some have went out in less than TWO. They MAY have purchased the lower end...Frank McElroy posted, I think, a Video on Lithiums and all Lithiums AIN'T the same.  Just like all batteries are NOT THE SAME.  The Trojan's are the GOLD standard.  Many brands are NOT that well made.  

So...that's it.  Color me what you want....but make sure it is NOT ANTI-LITHUM....but is ANTI-GAMBLING...  

Hope this clears it up.  

[Benjamin]

2 hours ago, Ivylog said:

I can’t explain why my alternator only charges my 600+AH of Lithiums 60-70 amps regardless of the SOC. Again, so much for the Experts.

Before I call BS, I like to make sure I know what is going on and why. 

"My understanding is the alternator does not put out full power unless there is a demand for full power, otherwise it only puts out what is needed, so hopefully there would not be an instance of the BMS shutting off while the alternator is pumping out 270 AMPS."  The alternator tries to maintain 14V, it puts out as many amps as it can if the load will take them at 14V.  That works with lead, Li is different, which is why smarter people than me say to not connect an alternator directly to Li.  

Edited August 13 by Benjamin

[RoadTripper2084]

5 hours ago, Benjamin said:

Before I call BS, I like to make sure I know what is going on and why. 

"My understanding is the alternator does not put out full power unless there is a demand for full power, otherwise it only puts out what is needed, so hopefully there would not be an instance of the BMS shutting off while the alternator is pumping out 270 AMPS."  The alternator tries to maintain 14V, it puts out as many amps as it can if the load will take them at 14V.  That works with lead, Li is different, which is why smarter people than me say to not connect an alternator directly to Li.  

Could many things. Cable resistance is commonly cited as a natural restrictor to alternator output, though in this that shouldn't be the issue, I wouldn't think.

We'd have to understand how the house batteries are connected to the alternator, usually the alternator charges the chassis batteries and they are connected to a battery maintainer or BIM of some kind to connect the chassis and house banks together when a charge voltage is present.

 

[Mocephus]

7 hours ago, RoadTripper2084 said:

Could many things. Cable resistance is commonly cited as a natural restrictor to alternator output, though in this that shouldn't be the issue, I wouldn't think.

We'd have to understand how the house batteries are connected to the alternator, usually the alternator charges the chassis batteries and they are connected to a battery maintainer or BIM of some kind to connect the chassis and house banks together when a charge voltage is present.

 

Hi Ken, on our rig, as I understand it without having the diagrams with me right now, the simplified path from the alternator is:

Alternator > Big Boy solenoid > Fuse > Internal BMS > Battery Cells

There’s also a Battery Isolation Manager in the mix. 

Edited August 14 by Mocephus

[Biljol]

The battery Isolation Manager may possibly have a max amps rating that is limiting the current.

In regards to battery boost to start, you can still use it kind of. When you boost you are connecting the two banks together. So what I have done is link them together for say 20 min this allows the lithium to charge the chassis battery. Then you can remove the boost and start.