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

[96 EVO]

Changed out my alternator this past winter, and went with another 160 amp.

Regretting that a bit now. Should have looked at future lithium batteries and upgraded to a higher output alt, even though I likely would have needed to upsize wiring.

[Grey Goose]

 

15 hours ago, Mocephus said:

Thanks Tom. Good thoughts and I’ll definitely reach out to LN. 

Your battery BMS may have an overall current limit, including the discharge/load current potentially limiting how much current the alternator could charge during a load event. 

A more pure test of charging capability would be to discharge the battery to say 10-15% and try charging with zero load on the house battery system. Turn the inverter and any dc loads off for the entire house system. 

[Biljol]

Electricity will always take the path of least resistance since it is less resistance to pull the power from the battery than the alternator then you have to look at it as power coming out of the battery to power everything. Then the alternator charging the battery. 

I still think ultimately the battery Isolator has a load limit. A 200A Battery isolator will usually split the difference so 100A max per leg.  So, the maximum Amps from the alternator to the house would be 50% of the Isolator ratting. you would need to look up the spec on the Isolator you have.

[Grey Goose]

16 minutes ago, Biljol said:

Electricity will always take the path of least resistance since it is less resistance to pull the power from the battery than the alternator then you have to look at it as power coming out of the battery to power everything. Then the alternator charging the battery. 

I still think ultimately the battery Isolator has a load limit. A 200A Battery isolator will usually split the difference so 100A max per leg.  So, the maximum Amps from the alternator to the house would be 50% of the Isolator ratting. you would need to look up the spec on the Isolator you have.

I suppose it depends on the design but mine was setup up to simply connect the two battery systems together but if the solenoid contacts were dirty it would in fact limit throughput. Another reason to do a pure charge test and not try to load the battery system while charging.  I am speculating that the battery BMS could also have a limit based on charge and discharge current.

Edited August 19 by Grey Goose

[Mocephus]

4 hours ago, Grey Goose said:

 

Your battery BMS may have an overall current limit, including the discharge/load current potentially limiting how much current the alternator could charge during a load event. 

A more pure test of charging capability would be to discharge the battery to say 10-15% and try charging with zero load on the house battery system. Turn the inverter and any dc loads off for the entire house system. 

Yes I considered the battery BMS but it’s rated at 200A max charge. It’s gotta be something though. I’m going to do a charging test on the house battery with no load and a 10-15% SOC. Maybe that will tell us something!

Edited August 19 by Mocephus

[Mocephus]

3 hours ago, Biljol said:

Electricity will always take the path of least resistance since it is less resistance to pull the power from the battery than the alternator then you have to look at it as power coming out of the battery to power everything. Then the alternator charging the battery. 

I still think ultimately the battery Isolator has a load limit. A 200A Battery isolator will usually split the difference so 100A max per leg.  So, the maximum Amps from the alternator to the house would be 50% of the Isolator ratting. you would need to look up the spec on the Isolator you have.

That makes sense Burke. I was kind of thinking about it the other way…alternator handles the load and any unused current going to charging the batteries.

I’ll see if I can get the specs on the BIM. 

[bryan browne]

On 7/22/2024 at 8:54 AM, 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.

 

I was also told By Vatrer to store my 2- 460ah batteries for a long period at about 50% charge.

[Mocephus]

On 8/18/2024 at 1:56 PM, Grey Goose said:

You could rerun the house load test with shore or gen power to see if the battery BMS behaves differently. Obviously you would need to come up with a way to load the house battery since you would not be on the inverter for the AC devices. This would tell you if the alternator in influencing the charge rate or the battery BMS.

I know you talked about rated charge rate but what have you observed when using your Xantrex charger?

I’m not sure what you’re asking about the Xantrex charger but I have noticed that it indicated the battery was full even when it was only at 70% SOC according to the BMS. Is that what you mean?

[96 EVO]

Good chance that's all you will get from a charger that thinks it's charging AGM or FLA batteries.

[pwhittle]

4 hours ago, bryan browne said:

I was also told By Vatrer to store my 2- 460ah batteries for a long period at about 50% charge.

I set my absorb and float voltages to 13.1V when parked plugged in, and that keeps the batteries around 50% charge. 13.3V is about 80%.

Paul

[Grey Goose]

1 hour ago, Mocephus said:

I’m not sure what you’re asking about the Xantrex charger but I have noticed that it indicated the battery was full even when it was only at 70% SOC according to the BMS. Is that what you mean?

I was curious how much current/charge rate when using the Xantrex. Just a way to compare to see if the BMS was influencing the charge rate as compared to the alternator. 

1 hour ago, Mocephus said:

I’m not sure what you’re asking about the Xantrex charger but I have noticed that it indicated the battery was full even when it was only at 70% SOC according to the BMS. Is that what you mean?

So it stopped charging at 70%? Will the alternator take it to 100% as indicated by the BMS? 

[Mocephus]

1 hour ago, 96 EVO said:

Good chance that's all you will get from a charger that thinks it's charging AGM or FLA batteries.

Actually it continued to charge the lithium until it reached 98% SOC. We arrived at our campsite last night with 72% SOC and hooked up to shore power. I checked the SOC just now (11:30PM) and SOC IS 92% with 0 charging amps. 

47 minutes ago, Grey Goose said:

I was curious how much current/charge rate when using the Xantrex. Just a way to compare to see if the BMS was influencing the charge rate as compared to the alternator. 

So it stopped charging at 70%? Will the alternator take it to 100% as indicated by the BMS? 

No, it continued to charge and took it to 98% SOC. I was pleasantly surprised!

[Grey Goose]

13 hours ago, Mocephus said:

Actually it continued to charge the lithium until it reached 98% SOC. We arrived at our campsite last night with 72% SOC and hooked up to shore power. I checked the SOC just now (11:30PM) and SOC IS 92% with 0 charging amps. 

No, it continued to charge and took it to 98% SOC. I was pleasantly surprised!

I asked this question initially to see if your battery SOC indicator was accurate or not. But also to see if you could measure the charge rate with the converter vs the alternator. If the charge rate in amps is similar for both then it might indicate the battery BMS or some additional resistance in your wiring or a connection is influencing the rate of charge. If you do this test I would try to do it with low SOC on house batteries and no load from inverter or other dc loads if possible.

Edited August 20 by Grey Goose

[Mocephus]

2 hours ago, Grey Goose said:

I asked this question initially to see if your battery SOC indicator was accurate or not. But also to see if you could measure the charge rate with the converter vs the alternator. If the charge rate in amps is similar for both then it might indicate the battery BMS or some additional resistance in your wiring or a connection is influencing the rate of charge. If you do this test I would try to do it with low SOC on house batteries and no load from inverter or other dc loads if possible.

Good ideas! I’m going to do that test tomorrow among some others with a low SOC on the house and no load if possible. That will be interesting to see the results. Stay tuned!

[Rick Chambers]

I have the ISL cummins with the 160amp alternator.  I installed the victron 30ap dc to dc charger when I installed Battle Born lithium.  I also installed the Victron Solar charge controller for the 600 watts of solar.  All has been working great for over 2 years now.

[Mocephus]

On 8/19/2024 at 2:35 PM, Mocephus said:

That makes sense Burke. I was kind of thinking about it the other way…alternator handles the load and any unused current going to charging the batteries.

I’ll see if I can get the specs on the BIM. 

Hi Burke, the Big Boy isolator relay is rated at 200A.

[Grey Goose]

3 hours ago, Mocephus said:

Hi Burke, the Big Boy isolator relay is rated at 200A.

The contacts in those tend to corroded so it could limit current. You might be able to tell if you check for a voltage drop across the two contacts while charging. 

Edited August 21 by Grey Goose

[Mocephus]

8 minutes ago, Grey Goose said:

The contacts in those tend to corroded so it could limit current. You might be able to tell if you check for a voltage drop across the two contacts while charging. 

Ok thank you. I'll check that!

[Ivylog]

If there’s more than 0.10V difference l, the contacts need cleaning.

[Tom Cherry]

1 hour ago, Grey Goose said:

The contacts in those tend to corroded so it could limit current. You might be able to tell if you check for a voltage drop across the two contacts while charging. 

The correct way to troubleshoot the Intellitec Big Boy as well as the BIRD circuit is as follows.

First...TURN OFF each bank.  Then turn on ONE bank.  Measure each stud to ground.  The one with POWER will be the bank that you turned on.  Label and mark the cables for future use.

With BOTH BANKS ON....NO AC (OR GENNY) and NO SOLAR....then measure the STUD to GROUND voltage.  There may be a difference when one bank is not fully charged.

Next...apply AC or GENNY.  The BIRD System should ENGAGE (GO CLUNK).  If you have the Intellitec BIRD DIesel2 System (2005 Dynasty and UP DO NOT USE THIS), then measure the Voltage across the Control (small) Contacts.  That should be in the 3 - 5 VDC range (It is PULSED...but a DVOM will average).  If it is a Dynasty, the NEGATIVE is actually Pulsed (why....beats me and other experts).  Doesn't matter Pulse the Negative or the Ground..  The Dynasty will read in the 6 - 10 VDC range.  A Dynasty Big Boy will chatter or HUM....loudly.  The Camelots and down with the BIRD Diesel2 will be quieter.

THEN use the HAND test.  The Dynasty, after say half an hour will be so HOT that one can NOT wrap and hold their hand around it.  AGAIN...this is NORMAL...

The Camelot and lower will be warm...but MUCH cooler and you can hold your hand on it.

NOW.....when the BIG BOY is CLOSED (is energized), then MEASURE the VOLTAGE across the STUDS.  If you get MORE than 0.2 VDC...actually 0.1 VDC should be the max...but it varies.......then the contacts are PITTED and a PM or teardown is needed.

Go to SEARCH.  Put in INTELLITEC (Big Boy might also work).  Then click on EVERYWHERE.  Chose FILES from the Drop Down.  There is a procedure on how to disassemble the Big Boy and clean it.  Folks with limited DIY or electrical skills have raved about how easy it was...and it took no more than 30 minutes and no special tools...just read and follow.

That's how it work...  GOOD LUCK...

[Grey Goose]

54 minutes ago, Tom Cherry said:

The correct way to troubleshoot the Intellitec Big Boy as well as the BIRD circuit is as follows.

First...TURN OFF each bank.  Then turn on ONE bank.  Measure each stud to ground.  The one with POWER will be the bank that you turned on.  Label and mark the cables for future use.

With BOTH BANKS ON....NO AC (OR GENNY) and NO SOLAR....then measure the STUD to GROUND voltage.  There may be a difference when one bank is not fully charged.

Next...apply AC or GENNY.  The BIRD System should ENGAGE (GO CLUNK).  If you have the Intellitec BIRD DIesel2 System (2005 Dynasty and UP DO NOT USE THIS), then measure the Voltage across the Control (small) Contacts.  That should be in the 3 - 5 VDC range (It is PULSED...but a DVOM will average).  If it is a Dynasty, the NEGATIVE is actually Pulsed (why....beats me and other experts).  Doesn't matter Pulse the Negative or the Ground..  The Dynasty will read in the 6 - 10 VDC range.  A Dynasty Big Boy will chatter or HUM....loudly.  The Camelots and down with the BIRD Diesel2 will be quieter.

THEN use the HAND test.  The Dynasty, after say half an hour will be so HOT that one can NOT wrap and hold their hand around it.  AGAIN...this is NORMAL...

The Camelot and lower will be warm...but MUCH cooler and you can hold your hand on it.

NOW.....when the BIG BOY is CLOSED (is energized), then MEASURE the VOLTAGE across the STUDS.  If you get MORE than 0.2 VDC...actually 0.1 VDC should be the max...but it varies.......then the contacts are PITTED and a PM or teardown is needed.

Go to SEARCH.  Put in INTELLITEC (Big Boy might also work).  Then click on EVERYWHERE.  Chose FILES from the Drop Down.  There is a procedure on how to disassemble the Big Boy and clean it.  Folks with limited DIY or electrical skills have raved about how easy it was...and it took no more than 30 minutes and no special tools...just read and follow.

That's how it work...  GOOD LUCK...

Yes, thank you. Even though I no longer use it I took care of my Big Boy PM about 1.5 years ago with good results. 

My post was for Mocephus who already knows his big boy is activating since he was able to charge his house batteries with the chassis alternator.

[Mocephus]

UPDATED HOUSE BATTERY TEST RESULTS (Shore, Solar and Generator) - I’ve completed some of the House Battery and charging tests y'all have suggested and here are the findings:

Epoch Lithium 300AH, 200A Charging Max, 200A Discharging Max. Big Boy Battery Isolation Relay max rating = 200A

SOC at start of test = 8% @ 13.1v

 

-Generator (Onan 12.5) on with engine off, shore power off, solar off = +37A

-Generator on, engine, shore, solar, inverter off, basic system load only = +50A

-Generator on with engine, inverter, shore and solar off, house switched on with load applied (Aqua Hot diesel furnace and blowers on, all lights and fans on) = +40A

 

-Shore on, inverter on, engine, generator, solar, refrigerator off , no load (basic system load only) = +35A

-Shore on, inverter on, engine, generator, solar off, load applied (refrigerator, convection oven, 3 exhaust fans, all lights, Aqua Hot 110) = +57A

 

- Solar on, engine, inverter, generator and shore off, no load (basic system load only) = +3A

 

Notes of interest:

 

- While discharging the House battery for the test, I was able to apply a -197A load by turning on the AH diesel furnace, all lights and fans, refrigerator and convection oven. At one time I saw the current jump to -211A at which time the BMS reduced the current to 60A for approximately 10 seconds and then returned to -197A.

- When I turned the House switch on, while on shore power, +37A went to the Chassis batteries and +55 to the House. Before I switched on the House, zero current was going to the chassis battery. Chassis SOC was 80% (12.5v).

- Generator sent +7A at 13.35v to the Chassis while testing the House charge scenario.

- With no external charging source, the Chassis battery was receiving +2.25A at 13.01v. Apparently the House was sending current to the Chassis.

- With the inverter switched off, the charger always stays on. Switching the inverter “on” at the inverter, turns the remote on.

I had a dickens of a time discharging the two Chassis batteries. I let it sit for hours with the LED headlights on but could barely get it down to the 80%. So, I didn’t have time to test the Alternator charging scenarios or the Big Boy Relay. I’ll do those tests a bit later!

Thanks in advance for your observations and conclusions!

 

 

 

[Tom Cherry]

On 7/21/2024 at 11:19 PM, Mocephus said:

Thanks Tom. I have the Xantrex RV3012.

In regard to your inverter….and this comment goes back to Page 1, I KNOW this as a fact for the Magnums…and it would appear to work that way for yours…but maybe I understood.

The Magnum and perhaps your Xantrex can NOT be turned off from the remote.  The inverter may be in “standby”, like a TV, but when there is an AC load applied….it turns on and begins INVERTING.  Many posts and much debate and misunderstandings and misinformation and also discussion with Magnum.

The only way to “turn off” is to either do two things.  ONE push the OFF BUTTON on the inverter.  Some find this confusing as if you don’t hold in the button properly…no JOY.  Magnum even says….safest way…hold in….do the SOFT RESTART.  That actually reboots the inveerter.  It does NOT RESTART….so leave it alone.  Do not push the start button.  NOW, the inverter is off.  I think that an idle Magnum will pull upwards of 5 A DC….when one has “shut it off” from the remote.  I know that when the Magnum is inverting, there is a 5% loss of available power or the inverter’s internal electronics requires 5% of the battery capacity to operate.

NOW…those numbers are “typical” and each manufacturer has specs and such.

BUT…just pushing the OFF button on an inverter’s control panel will rarely, I think, physically turn off the actual inverter itself.

Thanks for the info….

[RoadTripper2084]

12 hours ago, Mocephus said:

- With no external charging source, the Chassis battery was receiving +2.25A at 13.01v. Apparently the House was sending current to the Chassis.

This could be a problem since the LiFePO4 house battery will almost always maintain a higher voltage than the chassis. If this results in a constant drain from house-chassis it could be a problem as it could overcharge your chassis batteries and add a constant drain to your house battery. On the other hand, maybe it will act as an automatic battery-maintainer for the chassis, not certain...
 

On my Heart Interface Freedom 20 inverter (older sibling to the Xantrex?) there are dip switches on the back of the remote panel to configure its operation. One of these allows you to use the on/off switch on the front of the panel to manually enable the charger function (when external AC power is supplied via shore power or generator). When no external AC is available, the on/off switch controls the inverter function.  

Not sure of your model has the same features though, check the manual for your inverter.

[Grey Goose]

1 hour ago, RoadTripper2084 said:

This could be a problem since the LiFePO4 house battery will almost always maintain a higher voltage than the chassis. If this results in a constant drain from house-chassis it could be a problem as it could overcharge your chassis batteries and add a constant drain to your house battery. On the other hand, maybe it will act as an automatic battery-maintainer for the chassis, not certain...
 

On my Heart Interface Freedom 20 inverter (older sibling to the Xantrex?) there are dip switches on the back of the remote panel to configure its operation. One of these allows you to use the on/off switch on the front of the panel to manually enable the charger function (when external AC power is supplied via shore power or generator). When no external AC is available, the on/off switch controls the inverter function.  

Not sure of your model has the same features though, check the manual for your inverter.

I am also able to turn off my inverter functionality from my Magnum remote. It draws about 1/4 amps DC in off MODE as verified with an amp clamp at the inverter. 

It uses slightly more (1/2 to 3/4 amp dc) in "on" mode but ac breakers off. Breakers off is important when making this measurements because all your ac appliances have some drain even when turned off. 

Edited August 22 by Grey Goose