Lithium LiFePO4 Upgrade - 2020/21 Navion or View

[crah]

Originally Posted by misteracng

In regard to the solenoid or whatever it is, it might be needed as I would guess winnebago would not install it, unless lithionics requried it as a part of the lithium upgrade. Based on the wire labeling, I think the solenoid might be able to turn the chargepoint on and off so that the lithiums do not receive too much charge. I spoke with mastervolt tech and the chargepoint is not a multi0-stage charger, it does not adjust or change to a float charge, if the lithiums are full, so this may be the reason it is there. I did also learn that that a simple switch can be wired to the spade connectors on the chargepoint so you can turn it off manually or actually use it as an emergency jumper from the coach to chassis batteries.
Since that solenoid part might be difficult to get, I am thinkning it might be better to just replace the chargepoint with a proper DC-DC charger like a victron orion 12-30, then you have no worries about overcharging the lithiums.

If I really needed the chassis charging function, I would also switch to a proper dc to dc charger. I've also thought about installing a dc to dc charger/mppt charger combo. The solar wires already go under that passenger seat. All that would need to be done is rewire behind the existing charge controller which can easily done because winnebago put in the inline fuse back there so it can simply be rewired. Lots to contemplate. Now if I can get my new entry door (complete replacement required but under a recall) and all my exterior sealant redone, I can move onto the fun mods.

[misteracng]

I feel the same, I dont really depend on charging from the alternator. I think my main concern is will there be any issue to the lithiums in terms of potential overcharging from the chassis?

[Elkman]

I would contact the people at Battle Born and Lithionics and see what they say about the risk and if it does exist how best to resolve it. Battle Born sells the LI-BIM for use with lithium phosphate batteries that is designed to prevent a long continued charging of the house batteries from the alternator.

[crah]

I have to make one correction. I just traced the leveler wires and it does use the same black shielded cables that the solar wires use. So the black shielded cables in the battery bay is very well the leveler power like the diagram. The solar cable is under the passenger seat but I cut tell where it continues from the solar fuse.

[misteracng]

Originally Posted by crah

I have to make one correction. I just traced the leveler wires and it does use the same black shielded cables that the solar wires use. So the black shielded cables in the battery bay is very well the leveler power like the diagram. The solar cable is under the passenger seat but I cut tell where it continues from the solar fuse.

Thanks for the update, at least I can trust the winnebago diagram, felt strange they would make such a big error, I guess the solar runs somewhere else, didnt really see where it runs though.

I have been lookiing at the xantrex combiner wiring and the solenoid area under the passenger seat. It seems the combiner is sensing the ignition as well as connected to the coach battery disconnect switch. So maybe both of these need to be on for it too work. The solenoid wire goes to I think one of the relays under the seat. This might be connected to the solenoid next to it which is a coach disconnect relay. Its still confusing, best I can tell, the xantrex combiner would then allow chassis to coach charge if the ignition is on and the coach batteries are on. Seems to be some secondary way to charge the lithiums. I do see that the combiner does have a stop charging parameter, which the chargemate does not seem to have. However the chargemate has a switch connection that is optional and is indeed connected and being used in the winnebago diagram and I confirmed that it is connected physically on my coach. This switch allows the chargemate to be turned on and off. I dont know where the switch wire leads to. It may go to the same relay, so that when the xantrex is working the chargemate is off.
If this were true, it would seem like the chargemate in use while driving, with coach batteries disconnected, and xantrex combiner in use when driving and the coach batteries on. This is speculation from studying the diagrams. Also I really dont understand why this would need to be done either.

[Elkman]

Originally Posted by misteracng

I feel the same, I dont really depend on charging from the alternator. I think my main concern is will there be any issue to the lithiums in terms of potential overcharging from the chassis?

Check out the Battle Born website information on the Precision Circuits LI-BIM that they sell for use with lithium house batteries. It is designed to protect the house batteries when the alternator is producing current.

[misteracng]

Update on the lithium upgrade. I spoke with Winnebago, and the xantrex combiner part that is added with the factory lithium installation is used in between the chargepoint 40 that is standard and the lithium batteries. Winnebago said the chargepoint essentially just links the chassis and coach batteries together, both are standard lead-acid and it does limit charging to 40 amps max. The issue, is the lithiums do not like to be constantly cycled with small charging amounts up and down, so the xantrex unit prevents that. It allows the lithiums to discharge a bit more and then senses that to allow the chargepoint to connect and send current. So its not essential to ahve it, but its good in that it prolongs the life of the lithiums. That was the explanation from winnebago.

[rprochnow]

That may be an explanation, but the implementation is very poor because our lithium batteries were down to around 50% charge, and running the engine didn't provide any charging at all - even though the engine was on for an hour while we were driving.

A better implementation would be to start charging the lithium batteries when the engine starts - and then when they won't accept any more current, shut off the charging until the lithium batteries have been discharged enough to trigger charging again.

The implementation they've provided appears to charge the lithium batteries only if they are at a very low charge level (when the voltage finally starts to drop) - and that probably isn't the typical case...

[misteracng]

Originally Posted by rprochnow

That may be an explanation, but the implementation is very poor because our lithium batteries were down to around 50% charge, and running the engine didn't provide any charging at all - even though the engine was on for an hour while we were driving.

A better implementation would be to start charging the lithium batteries when the engine starts - and then when they won't accept any more current, shut off the charging until the lithium batteries have been discharged enough to trigger charging again.

The implementation they've provided appears to charge the lithium batteries only if they are at a very low charge level (when the voltage finally starts to drop) - and that probably isn't the typical case...

I'm not sure if its the best but that is what they are using. The xantrex combiner manual states it will charge if the chassis is >14V, and if the house batteries are >11.5 and <14V, so the cutoff to start charging is not too low. In your situation, that it did not charge, I was looking at the wiring diagram and it does show that one of the wires from the combiner goes to the coach battery disconnect switch near the stairwell. I think this switch must be on for the combiner to work as well. Perhaps that was the issue? It seems strange for this wiring. I'm not sure why its done, but its on the wiring diagram. This combiner is basically sitting between the chargepoint 40 and the coach batteries.

[rprochnow]

If the lithium batteries are being charged when the lithium voltage is below 14V, then they should be charging, even if the lithium batteries are close to full charge.

Doesn't explain why we didn't get any engine charge when our batteries were around 50%...

Have asked Lichtsinn to review this during our annual service in April.

[misteracng]

Originally Posted by rprochnow

If the lithium batteries are being charged when the lithium voltage is below 14V, then they should be charging, even if the lithium batteries are close to full charge.

Doesn't explain why we didn't get any engine charge when our batteries were around 50%...

Have asked Lichtsinn to review this during our annual service in April.

Yes you should have it looked at to be sure. It should charge when lithiums are below 14V. I wonder do you remember if your coach battery switch was on at the time? I'm not sure what the purpose of the combiner being connected to the coach battery switch is, but I assume the combiner will be off when the switch is off, and hence the chassis to coach will not be connected so no charging can take place. This is just my assumption based on the wiring.

[rprochnow]

Our coach battery and inverter are connected at all times. Even when we're in storage, because we have 110 power, we keep it all connected, though the inverter will drop into sleep mode.

So when we tried to charge from the engine, everything was connected.

Something doesn't seem right about this - and we'll get it checked. We're also not seeing as much solar power as we expected out of our 480W of solar panels on the roof - on a 100% clear sunny day, we're only getting around 180W of power - which also doesn't seem right.

Planning to look at this more thoroughly in April with Lichtsinn...

[Winnie-VIEW]

Hello


I have a 2019 View and the mastervolt chargemate pro 40amp DC-DC device. The online 2020 schematic for that device on winnebago's site shows wire LR connected to the switch terminal.



When the rig is running that LR wire (on both the 2019 and the 2020) sends a 12V signal to the chargemate switch, and that results in an "on" state for that device. Per the wiring diagram the 'ON' state is starting battery and coach battery shorted together just like when you press the boost mode switch... so there is no current limit on the alternator current supplied.


So..as of now if this is correct, I do not understand why the Factory installed the Chargemate pro 40 in this manner.


The downstream Xantrex relay that senses voltages and turns things on and off maybe helping prevent overcharge of the Li batteries in the coach, but you are not limiting the current from the MB alternator, unless I am misunderstanding how the Chargemate pro switch works.


I will contact Winnebago and try to learn more and post here... thanks if anyone understands how the chargemate pro current is limited, to protect your alternator... I do not at this time.

[Koert]

We have a 2021 Navion D and I've been trying to sort out why things are configured the way they are.

As best I can tell, many of the complexities are due to "legacy" wiring designs. (We used to have a 2007 View, and much of the wiring is exactly the same, and even that was probably brought to the View from other Winnebago models.)

Our wiring schema is apparently a combination of design, cables, and devices from other Winnebago models, modified to fit the View, and then with a bunch of workarounds to accommodate the 2021's lithium battery capability and inverter.

A standard installation for alternator charging would be to have a direct connection from the alternator (in our case, the Sprinter chassis bus) to a DC-Dc charger, and then to the battery.

Using the Mastervolt Charge Mate Pro instead of a DC-DC charger is acceptable, because even though it doesn't optimize the charging stages, it does limit the current and prevent it from flowing in the wrong direction. (The default setup works adequately and there's no reason to use the Switch or Ground terminals unless additional features are desired.)

The Battery Boost switch is omitted from the newer models, but the Mastervolt Charge Mate Pro can be wired to offer the same capability to provide a direct connection for jump starting the chassis battery from the coach battery.

The Battery On/Off switch, which works through a remote relay, adds needless complexity. To disconnect the batteries, a simple high-current rotary switch (the type seen on boats) would be much more durable and trouble-free.

And then, because the inverter requires heavier cables than the other DC circuits, it was necessary to install a second battery disconnect that's devoted strictly to the inverter. There's no reason why a single main battery disconnect couldn't be used.

We don't have the factory lithium battery option, but the Xantrex Combiner (actually a relay control) introduces a bunch of confusing logic, only activating the battery relay when certain conditions are met (Chassisbattery>14V Housebattery>11.5V Housebattery<14V), some of which seem to overlap with the Mastervolt Charge Mate Pro and with the batteries' BMS. (I'm pretty sure they put it there to meet some Xantrex/Lithionics battery technical requirement, but we don't have the factory lithium system, so it doesn't concern us.)

Not knowing the full details of Winnebago's wiring, I've been hesitant to start altering things too much, but I would like to remove the relays/solenoids under the passenger seat and clean up the alternator-charging circuit. (I've already abandoned Winnebago's solar-charging circuit and installed cables that go directly to the battery.)

[creativepart]

Originally Posted by Koert

(I've already abandoned Winnebago's solar-charging circuit and installed cables that go directly to the battery.)

Wait... you mean directly from the solar panels to the solar charge controller and then directly to your battery. Correct?

You can not direct connect solar panels over about 10-15 watts output directly to the batteries.

The standard 100w solar panels will overcharge and cook your batteries if you do not use a solar charge controller in the system.

[creativepart]

Originally Posted by Koert

And then, because the inverter requires heavier cables than the other DC circuits, it was necessary to install a second battery disconnect that's devoted strictly to the inverter.

Actually, the only time the inverter battery disconnect is used is when you need to disconnect your batteries for removal, etc.

If you disconnect your battery without disconnecting the power to the inverter you risk frying the inverter's electronics. It's pretty vital to do this.

Yes, using solenoids to do what a rotary disconnect can do is needlessly complex but it's to be expected on a motorhome like your Navion.

Don't forget that your inverter is also your RV's house battery charger - So, that inverter rotary switch must be on or your batteries will not charge on shore/generator power.

[Winnie-VIEW]

Originally Posted by Winnie-VIEW

Hello


I have a 2019 View and the mastervolt chargemate pro 40amp DC-DC device. The online 2020 schematic for that device on winnebago's site shows wire LR connected to the switch terminal.



When the rig is running that LR wire (on both the 2019 and the 2020) sends a 12V signal to the chargemate switch, and that results in an "on" state for that device. Per the wiring diagram the 'ON' state is starting battery and coach battery shorted together just like when you press the boost mode switch... so there is no current limit on the alternator current supplied.


So..as of now if this is correct, I do not understand why the Factory installed the Chargemate pro 40 in this manner.


The downstream Xantrex relay that senses voltages and turns things on and off maybe helping prevent overcharge of the Li batteries in the coach, but you are not limiting the current from the MB alternator, unless I am misunderstanding how the Chargemate pro switch works.


I will contact Winnebago and try to learn more and post here... thanks if anyone understands how the chargemate pro current is limited, to protect your alternator... I do not at this time.

I contacted Winnebago Tech Support, and they informed me that the LR wire is not really identical between the 2019 and 2020 rigs. It starts and ends in the same place but is not connected in the same manner, it goes to the Xantrex relay first, and the signal from LR to the Chargemate pro is just open, to operate in automatic mode, or shorted to ground to turn the unit off if the relay battery sense indicates the battery is full.


For Lithium Battery's there is an onboard BMS that protects the battery from over/under charge, or low temp charge, but the BMS just disconnects the battery from the rig when it trips, and then your refrigerator will not work.


So.. goal is near perfect battery charge inputs, and sensors external that monitor the battery voltages achieved and turn off charging before the battery internal BMS is triggered.


I also spoke to Mastervolt about the Chargemate pro 40 , and they indicated that is really was just a dumb current limiter, and to turn it on and off to prevent overcharge a relay and other additional voltage sensors are needed.


So.. it appears that Winnebago did take all that into account, and are using the Chargemate correctly, and turning it off and on as needed. I was just a little surprised that my initial consultation said, the LR wire is identical between the 2019, and 2020 coaches, and that is not correct.


So.. I now need to decide if I just switch to a more sophisticated Victron DC-DC charger to limit the alternator current as their version includes programming to turn the charge current on and off based on the downstream Lithium battery connected, and that is all contained in a single box you install and program, and can monitor with a blue tooth app.


Regards to all...

[Koert]

Originally Posted by creativepart

Wait... you mean directly from the solar panels to the solar charge controller and then directly to your battery. Correct?...

Yes, I abandoned Winnebago's convoluted wiring and ran dedicated and direct solar charging cables.

(My new configuration consists of four 210W panels - two of the panels in serial, the other two with their own cables - connected with MC4 connectors to three 10AWG marine duplex cables that go, uninterrupted to the battery compartment where there are three Victron controllers. The controllers are connected to a fused bus bar and that is connected to the main battery bus bar.)

[Koert]

Originally Posted by Winnie-VIEW

I contacted Winnebago Tech Support...

Hi Winnie (are you the Winnie that I know of?)

Hope you don't mind if I'm a bit brusque and take your comments one at a time. (I'm absolutely not an authority on this but I might raise some questions that help you.)

First, the 2019 didn't come with a Mastervolt Charge Mate Pro, so I'm assuming either you or someone else added it later.

The 2019's have a relay to make sure that the coach and chassis batteries aren't connected if the engine isn't running. There is no regulation of the voltage or current going to the coach batteries. They also have a Battery Boost switch that bypasses that relay, to allow the coach batteries to jump a dead chassis battery.

The 2020's have, instead, the Charge Mate Pro which only allows current to flow in one direction (from the chassis battery and alternator to the coach batteries). It also limits the current to 40 amps (because a big bank of lithium batteries is capable of drawing more current than the alternator can handle).

The typical installation of the Charge Mate Pro is to connect it in-line on the alternator cable. It doesn't need to be turned on to do its thing - it will only allow power to flow in one direction and it will limit the current from the alternator.

The Charge Mate Pro has a terminal that can be connected to a switch that allows it to be in its normal mode, manually disconnected, or manually connected with bi-directional current, limited to 150 amps (for jump starting, like the Battery Boost switch in the 2019's). But it's perfectly usable without the switchable terminal or the ground terminal connected.

You mention a factory installation and the Xantrex relay controller, so I'm guessing that you had the Winnebago lithium battery option installed later.

In the 2020's the factory lithium battery option is a confusing design and I haven't yet been able to find anyone who can explain to me why they use the Chargemate Pro instead of a standard DC-DC battery charger (the technical reps at Mastervolt were wondering the same thing) and why they felt inclined to include the Xantrex relay controller with its unusual charging logic.

In most lithium battery systems, the BMS is meant to be a backup safety measure, not a way to regulate charging current or voltage.

During charging, lithium batteries need to be protected from high voltage (although the alternator will never deliver too much voltage) but they don't need to be protected from slightly high current. As they charge up, they will accept less and less current (that's how you can tell when a lithium battery is charged) and eventually won't accept any more.

Unless you are trying to keep your batteries below an 80% state of charge, as some do, there's no reason to disconnect and reconnect the Charge Mate Pro. The Charge Mate Pro does adequately perform its most important function and the only advantage to installing a Victron Orion DC-DC is to have a more efficiently optimized charging profile. (The Charge Mate Pro will put out whatever voltage it is being fed. The Orion will reduce or raise the voltage to what is best for the battery, but won't turn on or off based on the precise current.)

For the small amount of amperage delivered by conservatively using alternator charging, I don't see the point in spending a lot of time or money trying to optimize it. Better to install another solar panel!

Winnebago's unusual (and sloppy) wiring design bugs me and I'd like to reduce it to five independent and orderly circuits.

Solar Charging
Alternator Charging
120V (Shore Power or Generator) Charging
12V Distribution from the Coach Batteries
120V Distribution from the Inverter (connected to the coach batteries)

I've not been brave enough to start ripping stuff out from under the passenger seat, but I'd like to get rid of the battery disconnect relay and any other unnecessary wiring.

What sort of 120V charging do you have? Do you still have the Progressive Dynamics Converter/Charger?

One of the biggest advantages of lithium batteries is that they can be charged very quickly, so it makes sense to change to a more efficient 120V charger. (Winnebago's wiring of the converter/charger is another thing that's tough to understand, because the design is based on older units with lead-acid batteries and small inverters.) The best recommendation seems to be to get a combination inverter/charger like they have in the newer Views, and discard the old converter/charger.

As I said above, I'm no expert so please do your own due diligence and confirm what I've said (which is tough because there's a lot of misinformation out there) but unless you are prepared to rip everything out and go with an all-Victron system (including controllers, batteries, and inverter), there's not much value to be gained in going with the Victron Orion and the all-in-one programmable controller.

[rprochnow]

Our 2021 24D has two Lithionics Group 31 125Ah batteries.

Lithionics sells 315 Ah and 320 Ah that are about the same width, less than twice as long and 1.5" taller.

Wonder if one of these batteries could be used in the View battery compartment instead of having two Group 31 batteries... It would provide more power than having two smaller batteries...