Batteries not charging after lithium conversion

[lduchesne]

Hi,

I've got a small problem and am hoping someone can help:

I installed two new Renogy 12v 100Ah to replace the stock marine batteries in my RV. After the swap, everything was back to normal.

I then upgraded the converter part of my WF-8955 with the PD4655LIV. After plugging everything back, everything works on the batteries.

When I plug in the shore power, I measure 14.6v on both terminals on the small DC panel that came with the PD4655LIV (good). On the batteries terminals though, I measure 13.14v, which is the current I get when unplugged (they are not fully charged).

So the 14.6v charging current doesn't make its way to the batteries. What I hear is a "click", about every 5-10 seconds. Looks like something between the converter and the batteries is not happy with the 14.6v.

I think I tracked it down to a small black component (see images) which seems to "trip" on and off whenever I plug in my RV to shore power.

I have no idea what it is really so any help would be appreciated!

[Rick the Rocket]

The black device in the center of the top picture is a 100 amp contact relay with a 12 volt coil. If have 12 vdc across the 2 small wires at the base the 2 studs at the top are connected internally. Check for the voltage at the coil wires, if it is cycling like you describe, trace it back to the source and find what is interrupting it. Possibly a circuit breaker is tripping and resetting due to a short on the way to the relay. I doubt that the 1 volt (~13.5 to ~14.5) increase in your system voltage is the problem.

[lduchesne]

Rick, those 2 small wires appear to be connected to the same terminal. I measured between those and the bus with the green wires, and got 13.14v (battery voltage). When I hear the clicking sound, it goes up to ~14.3, then back to 13.14.

Installation of the new DC panel and converter was done rigourously and I can't see where I would have a short.
I'm looking at it right now and it is all nice and tidy. I think I'll have to contact Progressive Dynamic and see if they can help :/

[Rick the Rocket]

Okay I see the tabs are on the same terminal now. The other side of the coil is grounded to the metal bracket. So the bracket must be the grounded is the surface it is mounted to metal and grounded?

[Rick the Rocket]

Here is a data sheet on the relay, the way I looked at the picture I thought it had 2 terminals for the coil.
https://assets.alliedelec.com/v15645...77dab719f2.pdf

[lduchesne]

Interesting quote from the datasheet:

caution must be used in coil selection for use in 12 volt systems where battery charging may expose coil to continuous, higher-than-rated voltage. stancor will not be responsible for consequences of misapplied solenoids.

Do you think that this 1v difference might be just enough to be out of spec?

[Rick the Rocket]

The coil voltage spec is 12v at 14 the current would raise by about .2 amp. I re-read the caution, yes that is interesting. You may have open coil when it heats up.
Is the contactor actually opening and closing? When open you should have battery voltage on one and converter voltage on the other stud. When closed the voltage should be the same on both terminals.

[lduchesne]

It doesn’t stay closed long enough for me to measure a significant voltage difference (it gets a tiny bit higher before opening again).

I also found this data sheet, with a similar warning:

CAUTION must be used in coil selection for use in 12 volt sytems where battery charging may expose coil to continuous, higher-than-rated voltage. 14 volt coils are recommended.

I will call either Progressive Dynamic or Coachmen on Monday to confirm wether or not I would be better off with a 14v version of this solenoid. My only concern is that this might also used for charging with the alternator when driving, and I don’t know if the output will be >= 14v.

[TitanMike]

Originally Posted by Rick the Rocket

The black device in the center of the top picture is a 100 amp contact relay with a 12 volt coil. If have 12 vdc across the 2 small wires at the base the 2 studs at the top are connected internally. Check for the voltage at the coil wires, if it is cycling like you describe, trace it back to the source and find what is interrupting it. Possibly a circuit breaker is tripping and resetting due to a short on the way to the relay. I doubt that the 1 volt (~13.5 to ~14.5) increase in your system voltage is the problem.

Lithium batteries will draw the full output of the converter which in this case is 55 amp. If there is a self resetting circuit breaker in the circuit that is less than this amount it could account for the on-off behavior.

[lduchesne]

Originally Posted by TitanMike

Lithium batteries will draw the full output of the converter which in this case is 55 amp. If there is a self resetting circuit breaker in the circuit that is less than this amount it could account for the on-off behavior.

Oh if that is true, then I’m confused here

The main breaker for my RV is 30 amp, although my panel is a WFCO-8955 (55 amp). So I installed the PD4655LIV which was the recommended one. Does it mean I should have gone for the lowest model, which is the PD4635LIV? That is 35 amp, which is still over 30 amp though.

[TitanMike]

Originally Posted by lduchesne

Oh if that is true, then I’m confused here

The main breaker for my RV is 30 amp, although my panel is a WFCO-8955 (55 amp). So I installed the PD4655LIV which was the recommended one. Does it mean I should have gone for the lowest model, which is the PD4635LIV? That is 35 amp, which is still over 30 amp though.

Don't confuse the main breaker in the power distribution panel for a breaker in the battery charge circuit (12 V)

The '55' in the model number of the converter(s) is it's DC output current rating.

The 30 amp breaker is for the shore power input to the RV.

Somewhere along the wire from the batteries to converter there is usually a DC circuit breaker, often a 30 amp size. If you have one of these I'd make it #1 suspect.

[lduchesne]

Originally Posted by TitanMike

Don't confuse the main breaker in the power distribution panel for a breaker in the battery charge circuit (12 V)

The '55' in the model number of the converter(s) is it's DC output current rating.

The 30 amp breaker is for the shore power input to the RV.

Somewhere along the wire from the batteries to converter there is usually a DC circuit breaker, often a 30 amp size. If you have one of these I'd make it #1 suspect.

Thanks for the explanation, I didn’t know it was 55amp on the DC side of things. I’ll try to follow the wires tomorrow and see if I can spot a circuit breaker.

[Rick the Rocket]

The breaker titanmike is speaking about is usually shortly after the battery connection. Mine was at the end of my red battery cable. What trailer model are you working on?

[lduchesne]

Originally Posted by Rick the Rocket

The breaker titanmike is speaking about is usually shortly after the battery connection. Mine was at the end of my red battery cable. What trailer model are you working on?

So I traced the wires from the DC distribution panel, which has the right voltage, to the coil that trips, and then to the battery. I couldn't find anything in between any of those components
I even looked behind the whole electrical panel and nothing either.

The only thing remotely related I found is the relay in the attached picture. I say remotely related because it uses the same yellow striped red/brown/white, like in my first pictures.

Also, this is a coachmen leprechaun 260ds.

[Rick the Rocket]

I'm not that familiar with class c layouts. If the battery is connected like a bumper pull there is a breaker between the battery and everything else. You would think it would take the 55 amp that the factory set it up with. Start at the battery and follow the red cable until you find it. I'll put a picture in the next post.

[TitanMike]

Since it's been revealed that this is a Motorhome, they usually incorporate a means of isolating and charging the Starting Battery from the House Batteries.

You are most likely going to have to upgrade that system to a Lithium compatible system.

Others here that have done this can offer more help than those of us that have Trailers which are a lot more basic.

[Rick the Rocket]

This is the breaker they are auto reset many times.

[rk06382]

Originally Posted by lduchesne

Hi,

I've got a small problem and am hoping someone can help:

I installed two new Renogy 12v 100Ah to replace the stock marine batteries in my RV. After the swap, everything was back to normal.

I then upgraded the converter part of my WF-8955 with the PD4655LIV. After plugging everything back, everything works on the batteries.

When I plug in the shore power, I measure 14.6v on both terminals on the small DC panel that came with the PD4655LIV (good). On the batteries terminals though, I measure 13.14v, which is the current I get when unplugged (they are not fully charged).

So the 14.6v charging current doesn't make its way to the batteries. What I hear is a "click", about every 5-10 seconds. Looks like something between the converter and the batteries is not happy with the 14.6v.

I think I tracked it down to a small black component (see images) which seems to "trip" on and off whenever I plug in my RV to shore power.

I have no idea what it is really so any help would be appreciated!

Originally Posted by lduchesne

So I traced the wires from the DC distribution panel, which has the right voltage, to the coil that trips, and then to the battery. I couldn't find anything in between any of those components
I even looked behind the whole electrical panel and nothing either.

The only thing remotely related I found is the relay in the attached picture. I say remotely related because it uses the same yellow striped red/brown/white, like in my first pictures.

Also, this is a coachmen leprechaun 260ds.

Now that I know you have a class C. Your "click" is probably your BIRD.

You will need to upgrade your BIRD with a LiFePO4 Battery Isolation Manager (BIM).

https://battlebornbatteries.com/prod...ation-manager/
Features
The LiFePO4 Battery Isolation Manager (BIM) monitors voltage and connects batteries when needed. Under normal charging conditions, the BIM will connect for 15 minutes every 35 minutes. That means that the BIM will connect for 15 minutes, disconnect for 20 minutes, and repeat this cycle until the coach battery is charged.

If the coach battery resting voltage exceeds 13.4 V then the BIM will disconnect. A resting voltage greater than 13.4 V indicates a fully charged battery. Note that “resting voltage” means that no current is flowing to the coach battery.

The BIM will disconnect if the alternator voltage exceeds 14.4 V. This protects the coach battery from over charging. The LiFePO4 Battery Isolation Manager will disconnect if the voltage difference between the alternator and the coach battery is less than 0.1 V. If the voltage difference is too low, then there is a negligible charging current, and no need to connect to the coach battery.

The BIM will disconnect if the alternator voltage drops below 13.3 V. If the alternator voltage is too low, then it cannot adequately charge the coach battery, so there is no reason to connect.

The voltage differences between Lead-acid & LiFePO4:


See my post: How to adjust SDC-107A BCC for Battle Born batteries

After modifying my SDC-107A BCC for LiFePO4

[lduchesne]

@Rick I looked again but couldn't find anything inline with those wires, anywhere.

@Mike Sorry I should have mentioned it was a motorhome. I realize now it makes this a bit more complex.

@rk06382 It sounds like you might be right. I was just reading that the current demand from the lithium might be high and that my alternator may get pretty hot when idling.. do you find that is a problem with your RV? I wasn't able to locate my exact model but the smallest standard one on a Ford E450 SuperDuty cut-away DRW seems to be 150 amp at full speed.

I'll have to read a bit about how to plug things on that LiBIM225. In the picture I sent, there are quite a few more wires than terminals in the LiBIM225.

Originally Posted by rk06382

Now that I know you have a class C. Your "click" is probably your BIRD.

You will need to upgrade your BIRD with a LiFePO4 Battery Isolation Manager (BIM).



The voltage differences between Lead-acid & LiFePO4:


See my post: How to adjust SDC-107A BCC for Battle Born batteries

After modifying my SDC-107A BCC for LiFePO4

[lduchesne]

Hi,

So I finally got around to install this today. I attached an annotated picture of the original setup, and a picture of the new setup. The only thing I had to add was that green wire, which I grounded on the frame. I hope this can help someone in the future. Also, it is pretty tight because I wanted to reuse the same plastic cover that goes over this setup, and it still fits nicely.

The good news is: I tested this setup and it works perfectly for charging the lithium batteries using the alternator, while running the truck.

The bad news is, my converter is STILL not able to charge the batteries. I get exactly the same behavior as before, just at a faster rate (and more silent "click" from the Li-BIM 225).

The output at the converter is still 14.6V, and the battery V goes up just a tiny bit before going back to the original baseline value.

I tried to contact Coachmen via their web contact form, no reply. I tried Jason (rep for Leprechaun by email), no reply. I left a message today to his voicemail, no reply. I'm at a loss here on how to get a wiring diagram. This guy is not replying at all.

As some of you suggested in the past, I did try to find some inline fuse but really there is nothing but wires here. I just can't find anything on the circuit.