1984 GMC Van Lithium Battery Converter Upgrade

[SOCK MONKEY]

We've had this Van for a few years now and it is mostly all original wiring and stuff. It has the original Progressive Dynamics 15 Amp Power Converter with a 2.5 DC output going to 2 1 AMP inline fuses. It also has 1 15 Amp 120 volt breaker.

I came with 2 6Volt Marine deep cycle batteries. They were probably 15 year old and end of life.

Everything worked fine other than dry camping involved trying to keep the batteries charged with my Canadian Tire Solar panel. I had both a little charging device and it seemed to work as long as we had a sunny day.
The Van had very minimal electric needs just a few old school tail light bulb fixtures, a cheap 12volt fan and range hood fan. Then the 3 way fridge which of course we ran on Propane when parked, 12 Volt while travelling and Then AC when available.
The first upgrade was swapping out the old light fixtures for LED's. Next is I just upgraded to the Power Queen 100Ah Lithium Batteries.
But now The problem is my old Converter is supposedly bad news for the new battery.
I couldn't find any 15 amp converters so I ordered a 30 Amp. from Amazon. But when I opened the box and looked it over it didn't have any CSA or UL sticker anywhere. And it used weird breakers. I sent it back and this is why I am posting.

I'm trying to find a reliable source for a 15 Amp Converter.

My son who is an electrician thinks I should just keep the old converter and buy a proper Lithium charger and rig that up. But as you know this is not that straight forward in an RV. The Battery still need to go to the Converter to feed the 12Volt system.

So I'm at a point where a proper Converter would still be the easiest solution but I'm also thinking that there is also ways I could isolate the charging system from the 12 Volt system.
Option 1- All the 12 volt is directly connected to the Battery. I simply keep the battery charged using either my Solar panel or a 120 Volt charger.
There's more but I will leave it at this and hopefully I can find a proper 15 Amp Converter.

 

[Utclmjmpr]

Grand Forks sounds familiar,, I spent from 1959 to 1963 in the Forks , both west and east before the great flood.. I also remember the 50 below temps..>>>Dan

 

[Mark_K5LXP]

You've got some pondering to do. Engineer a soluton to be minimally invasive and accommodate the faults and frailties of the existing system or go scorched earth and bring it up to modern standards. Having done a lot of vehicle wiring over the years, scorched earth is usually the better choice. Just sayin', what your asking for is possible but likely more difficult and with a nominal end result

Mark B.
Albuquerque, NM

 

[SOCK MONKEY]

Thanks for your reply. There's actually nothing wrong with the 12 volt system. It's a bit messy in places but it's all good quality and no corrosion. Now the lights are LED the wiring is actually overkill.
Here is a diagram of a very feasible system. This allows for keeping the old Converter, which is probably better quality than anything new under $300, and isolating the Converter and the Lithium battery from each other.

The 120 Volt system remains untouched.

For the 12 volt it would involve nothing more than a commonly found Fuse strip and a toggle switch. The Fuse strip would be located where all the 12 Volt wires are terminating already. Actually almost no new wiring would be required. Simply re route the Battery input to the converter to the new switch and fuse strip.

This would be no different than the existing set up where there is a switch marked Battery / Converter that I always have to toggle when plugging in. My last RV ( Bigfoot) this was automatic. I might even be able to hack into that switch! I'm going to remove the converter and take it apart anyway. Make sure it's still looks safe.
Only one technical detail is the feed from the Van's battery that has a relay and charges when you are driving. I believe the relay turns off when the voltage drops below a certain threshold. Possibly there is information on converting this for lithium charging systems which is said to be different.

 

[Mark_K5LXP]

There is no redeeming feature to an 80's converter. If it was anything more than a transformer and a rectifier I'd be surprised. Limited current and crappy regulation. By all means, a new converter is on the list. A lithium converter will handle both battery charging and house loads.

Rewire your battery-converter switch so that the loads are always connected to the converter and the switch connects and disconnects the battery. There is no useful purpose switching the converter between the two.

I would include some form of battery monitor for basic system status.

Mark B.
Albuquerque, NM

 

[SOCK MONKEY]

My son the electrician agrees with you @Mark_K5LXP so thanks for you input.
He is going to look into finding me a good Charger that will also manage the power from the Solar panel. The old Converter will be scrapped.
We will wire the 120 V AC directly into the Fridge and AC outlets properly. We don't plan on ever having Air Conditioning. The van is just to get us there and sleep in. We don't live in it. With the new powered ceiling vent it feels very cool even when its 80 out.

 

[John From Detroit]

Two devices are needed.
one is a solar charge controller MPPT type should work best (maximum power point transfer if I got the order correct)

And a good 3-4 Stage mains to DC converter like a Progressive Dynamics 9200 series
for lead acid look at 92xx were xx is about 1/4-1/3 the battery amp hour capacity.

For LiFePO4.. I'm not sure the size but PD makes a different converter for those.

I do like PD converters... (Though I do admit to a bit of bias in favor of companies in Michigan)

 

[OldWEB]

https://www.progressivedyn.com/wp-content/uploads/2017/04/688-owners-manual.pdf

 

[Mark_K5LXP]

finding me a good Charger that will also manage the power from the Solar panel.

I'm not aware of any such thing, per John you're after a solar controller with a lithium mode, and a converter with a lithium mode. For these nominal power draws you may be smashing flies with a hammer installing a 45-55A converter, I might entertain just a basic supply with current limiting but you may not want to go down that rabbit hole. Solar is another topic entirely, not sure what your goals are there. I find that it's a solution with a very narrow scope of problems to solve, generally not worth the trouble or expense. So the controller and/or panels you get should be treated as a separate project.

Mark B.
Albuquerque, NM

 

[SOCK MONKEY]

Yes I have quickly come to that conclusion. I have a basic Solar charger that is working fine. I only used it on the old Lead acid. But seems I shouldn't be using it. Mine is the model without a remote.


This is what Google says:

• • Lithium-Compatible Versions: Huine makes a specific version (often supplied with an infrared remote control) explicitly rated to support 3S or 6S Lithium-ion and 4S or 8S LiFePO4 batteries, alongside lead-acid. For these models, you must use the remote control immediately after activation to manually select the correct lithium setting, as the default is lead-acid. [1, 2]
  • Lead-Acid Only Versions: The standard, basic IP68 models (typically identified by having 3 simple status LEDs and no remote control) are strictly designed for Lead-Acid (Sealed, AGM, GEL, or Flooded) batteries. Their manuals explicitly state they are not suited for lithium-ion or other battery chemistries.
  I have a proper charger for the Battery but it is only a 2Amp trickle charger. The Battery instructions say I should use a 10 Amp Converter. I will go shopping for those 2 items. Thanks for your feedback.

 

[SOCK MONKEY]

For these nominal power draws you may be smashing flies with a hammer installing a 45-55A converter,

This all started posting here looking for a 15 AMP Lithium compatible Converter. All I could find were 30 AMP and bigger. My Fridge is the only big draw and it says I need 10 Amps. The plan now is to purchase a LifePO4 charger that is 15 Amp. And a new Solar controller too.
For the AC my son is making me a 20 AMP / 15 Amp panel we will mount where the old Converter was.

 

[Mark_K5LXP]

The feature to look for with the charger is if it can operate loads without a battery connected. Many chargers don't operate that way. Otherwise you'd have to leave the battery connected all the time, which isn't a show stopper but you'd have to consider how you'd operate and isolate it that way.

Mark B.
Albuquerque, NM

 

[SOCK MONKEY]

The feature to look for with the charger is if it can operate loads without a battery connected. Many chargers don't operate that way. Otherwise you'd have to leave the battery connected all the time, which isn't a show stopper but you'd have to consider how you'd operate and isolate it that way.

Mark B.
Albuquerque, NM

Yes I Emailed the manufacture and they promptly replied that the charger I have ordered has this ability as long as I don't draw much over 10 AMPs. As it is I doubt I'll be drawing 2 Amps. The Fridge is the only 10 Amp appliance and it will be on 120 Volts when the 120 Volts is available.
As it is there is no 12 Volt wire that runs directly from where the Converter was to the Fridge.

I'm just sorting all that out. The fridge 12volt wire goes to the front. It's pretty complicated if you try and trace the wires under the hood. Two Solenoids and 2 Relays and a whole rats nest of wires to the battery and through the firewall. From what I understand this is the system that protects the front battery from being drained by the Coach system.
I'm just now fully charging the Van battery and then will test if there is power to the fridge with the motor running. Right now that wire is dead. That's actually a good sign.

The other wire went to the converter and then to a relay ( Diode? ) then the Coach battery. So that was obviously the charge while driving system. But I can't use that as is because it is incompatible now. It also has no power to it but I'm expecting power once I run the motor for a few minutes. I will look into a possible add on that would make this power safe to use with the Lifepo4. Actually a second Solar Controller like the one I just ordered might work?

This is what I have ordered.