Going Lithium questions - Page 2

RACarvalho · 02-06-2022, 05:53 AM

Quote:

Originally Posted by BASSMAN

I am using the Renogy 60 amp DC to DC charger...

Thank you Bassman,
If that battery I put the link is not reliable (which seems it is not), then I'll default to plan A and just install 3 group27 VMax Tank batteries.
The only time we really need the battery capacity is for 5 or 6 overnights / year at Walmart and I'm willing to do the work to change the converter and install the DCDC charger/relay to move to Lithium but for just those few nights the higher price of the lithium doesn't make sense.
That is too much $ for 60 overnights in 10 years...
The Vmax tanks can last 10 years ....
I already bought a Victron 712 battery monitor and will be installing that though.

ScottyB410 · 02-06-2022, 01:41 PM

Quote:

Originally Posted by RACarvalho

Scott,
The discussion is to get rid of this and install a DCtoDC charger which limits the charge current so there is no risk for the alternator.
The problem with this solution is that it eliminates the "emergency start" feature that the MH have.
To keep that, a relay is needed ...

OK, now I follow what you are saying. Thanks for that.

Kyis · 02-27-2022, 05:53 PM

First time here. HI!

I agree with dc to dc charger is way to go. If you remove bim will house charger still charge chassis battery? or does something else control that?

I'm in the middle of setting up my lithium upgrade.
So far 200ah, smart victron dc to dc and a victron ac to dc charger. (remove house charger) No solar yet and maybe never.
My thinking so far, and it has been a lot, is I like the victron as I want to able to set my own voltages for charging. Mostly because I hoping to have less battery cycles and store batteries at about 50% charge while on shore power or in storage for longer life. Also want a lower charge rate from my alternator. Of course everyone camps differently.
Also question about bim. If i just disconnect the ignition wire wouldn't it still have the emergency start and just wont charge anymore to coach batteries?
I Might have to call precision.
Thanks so much for any help.

bevedfelker · 02-27-2022, 07:43 PM

I hate to be a Debby Downer, but --
- could damage the alternator,
- could require a different BIM,
- could require rewiring,
- could require lithium battery heaters,
- could require a new Dc to Dc charger,
- could require some relays because of heavier load,
- could require extra fire extinguishers to put the fire out,
- could require an advanced degree in electrical engineering.
- did we even address solar added to it?
- will I still be able to extend the awning/
- geez, I just wanted to make a cup of coffee.

All those "coulds" must include cold cost a few thou from the pocket change in the couch.

... and NO, I do not intend to add it to the Axis/Vegas Owners manual I compiled.

But good luck guys, post your results while us Debby Downers can continue to guess what position our USE/STORE switch should be in.

RACarvalho · 02-27-2022, 11:10 PM

Quote:

Originally Posted by Kyis

First time here. HI!
If you remove bim will house charger still charge chassis battery? or does something else control that?

If i just disconnect the ignition wire wouldn't it still have the emergency start and just wont charge anymore to coach batteries?

Removing the BIM:
As far as I understand from the Thor schematics on my MH, if you remove the BIM, the house charger will not charge the chassis battery.

Disconnecting the ignition wire:
Again, as far as I understand how the BIM works, the ignition wire is a "signal" wire that tells the BIM that it can connect the the two batteries WHEN a certain set of parameters trigger that....
If the ignition wire is not there, the BIM will not connect the two batteries when the coach is running and charge the House battery from the alternator while on the way...
It may (needs confirmation from Precision), however, connect and charge the chassis battery from the onboard charger when plugger to shore, I think...

RACarvalho · 02-27-2022, 11:27 PM

Quote:

Originally Posted by bevedfelker

I hate to be a Debby Downer, but ....

Thank you for your contribution.
As a matter of fact I just received 3 VMax tank batteries (lead Acid AGMs) that I'll, God willing, be installing next weekend.
The reason I decide to keep the system as it is and just install new batteries was three fold:
1 - I could not certify a relay to work with the emergency buttom.
2 - Laziness: It will be a lot of work and we don't do boondocking .
3 - Cost: Too high for something We dont need.

That being said, several people do it and report success...

Kyis · 03-01-2022, 06:18 AM

Quote:

Originally Posted by RACarvalho

Removing the BIM:
As far as I understand from the Thor schematics on my MH, if you remove the BIM, the house charger will not charge the chassis battery.

Disconnecting the ignition wire:
Again, as far as I understand how the BIM works, the ignition wire is a "signal" wire that tells the BIM that it can connect the the two batteries WHEN a certain set of parameters trigger that....
If the ignition wire is not there, the BIM will not connect the two batteries when the coach is running and charge the House battery from the alternator while on the way...
It may (needs confirmation from Precision), however, connect and charge the chassis battery from the onboard charger when plugger to shore, I think...

Thanks for the answers.
I spoke with precision today. Surprisingly without the ignition wire he says the unit is still somewhat operational and won't operate as quickly as normal. The emergency start function would continue to work. There's a lot going on inside that little Bim.

RACarvalho · 03-01-2022, 01:36 PM

Quote:

Originally Posted by Kyis

Thanks for the answers.
I spoke with precision today. Surprisingly without the ignition wire he says the unit is still somewhat operational and won't operate as quickly as normal. The emergency start function would continue to work. There's a lot going on inside that little Bim.

Thank you for letting us know!

Chance · 03-01-2022, 05:28 PM

Quote:

Originally Posted by bevedfelker

I hate to be a Debby Downer, but --
- could damage the alternator,
- could require a different BIM,
- could require rewiring,
- could require lithium battery heaters,
- could require a new Dc to Dc charger,
- could require some relays because of heavier load,
- could require extra fire extinguishers to put the fire out,
- could require an advanced degree in electrical engineering.
- did we even address solar added to it?
- will I still be able to extend the awning/
- geez, I just wanted to make a cup of coffee.

All those "coulds" must include cold cost a few thou from the pocket change in the couch.

... and NO, I do not intend to add it to the Axis/Vegas Owners manual I compiled.

But good luck guys, post your results while us Debby Downers can continue to guess what position our USE/STORE switch should be in.

All valid concerns that can be addressed easily by design engineers prior to motorhome being built. Doing it right from onset is most cost-effective approach, and allows all electrical components to be selected properly and optimized for lithium-battery use. It’s possible to upgrade pretty much anything, but the cost/benefit ratio is much higher if done afterwards.

I agree most people can enjoy their present motorhome as is, and wait to upgrade at time of next purchase. Most owners probably lack the knowledge and skills required to upgrade electrical system themselves, and would have to pay others which adds even more to total project cost.

Some here have the skills, but I would bet they are a small minority of owners. Like you, I have hard time justifying an upgrade.

RACarvalho · 03-08-2022, 02:48 PM

Ok, So I just installed 3 x VMAX Tank XTR27 batteries and a Victron 712 Battery Monitor this past weekend...

I noticed that when the battery disconnect is off, the battery will not charge even if you are plugged to shore power but a 7W load is draining the batteries.

I went to the Victron manual and the manual states that the battery monitor should consume 1mA in stand by...

everything in the coach is turned off and the battery disconnect is in off so I was expecting a zero load on the batteries....

Does anyone have an idea where this 7W load may be coming from?

Tks,
R

BASSMAN · 03-08-2022, 06:10 PM

RACarvalho, I just sent back the third Victron 712 Battery monitor, I have been working with them on the monitor resetting its self to 100% after 2 hours of use and no charger hooked up, this monitor is suppose to be top of the line and my problems are different from yours, I had to take pictures of everything and the way its wired, we tried several fixes and then was told to just send it back, are you using the battery temp connector or just the small red wire to power the memory of the monitor? Unhook either the temp connector or the small red wire and see if you draw goes away, also in your smart phone app when you go to tools and then battery there is a button at the bottom for an automatic reset to 100%, in default its on and the dealer told me to turn it off

**16ACE27** · 03-08-2022, 06:17 PM

Quote:

Originally Posted by RACarvalho

Ok, So I just installed 3 x VMAX Tank XTR27 batteries and a Victron 712 Battery Monitor this past weekend...

I noticed that when the battery disconnect is off, the battery will not charge even if you are plugged to shore power but a 7W load is draining the batteries.

I went to the Victron manual and the manual states that the battery monitor should consume 1mA in stand by...

everything in the coach is turned off and the battery disconnect is in off so I was expecting a zero load on the batteries....

Does anyone have an idea where this 7W load may be coming from?

Tks,
R

CO/Propane/Smoke Detectors?