Relion LiFEPO4 house batt - No traveling charge

[Flintstone]

My 2017 2391 TS (Ford Transit chassis) was built with a Relion RB100 lithium house battery. I was told 100 were produced this way. (so, at least 500, right?)

It’s designed NOT to charge, going down the road, en rout, and it does so perfectly

And is a very obscure and hard to understand thing.IMHO
Without a Victron BMV702 or other decent ammeter

It doesn’ charge because the Ford alternator voltage is too high!???
It doesn’t charge because everything is working exactly as its supposed to?
See what I mean? it’s odd. it’s not like a missing sink or something
I don’t think most people would Ever even notice, or know where to start

The ‘lithium’ BIM inside the Precision Industries Battery Control Center engages (and closes the switch, connecting the house battery to the chassis battery, & charging) between 13.5-14.4 volts. The Ford Transit charges at 14.5. (in other words, it never charges)

The Sterling BB1260 was recommended and tested but doesn’t account for the thirstiness of the lithium yet and burns itself up.(as of Jan2018 ver.)

The Victron Buck Boost is my next stab in the dark, more on that later

I’d like to find at least 5 others, of that alleged ‘100’, to help me sleep at night, or just one other person who has it working somehow and doesn’t mind sharing.-)

Thanks

[JLeising]

Don’t have anything like your unit, but find your issue fascinating. Thought of adding a resistor in the wire from the alternator to the BCC? Seems like a small (1 ohm?) resistance would drop the supply voltage seen by the BCC to within the range you mentioned. E.g.:
https://www.amazon.com/Cutequeen-Alu...+watt+resistor

Assuming it charges from shore or generator power, an alternate solution might be to use an inverter off your chassis battery to power your house charger (or a separate Li battery charger) while “going down the road”.

Good luck -

Jim

[Flintstone]

Originally Posted by JLeising

Don’t have anything like your unit, but find your issue fascinating. Thought of adding a resistor in the wire from the alternator to the BCC? Seems like a small (1 ohm?) resistance would drop the supply voltage seen by the BCC to within the range you mentioned. E.g.:
https://www.amazon.com/Cutequeen-Alu...+watt+resistor

Assuming it charges from shore or generator power, an alternate solution might be to use an inverter off your chassis battery to power your house charger (or a separate Li battery charger) while “going down the road”.

Good luck -

Jim

Appreciate the thoughts
the resistor might work, but seems like that would soak up most of my precious 50 amps and turn into a toaster, there’s gotta be something like that, tho, I like the way you think

The BB1260 v1.0 is like that, kind of, like, a 25% solution, if you want to cycle it on and off every few miles and make coffee at the same time

A bunch of us bought these things new, recently, ‘complete’,
I’m holding out for something properish and professional -like and fool proof, like we all thought Forest River would have done it the first place, i even think they’d stand behind me a little, at least that’s my plan

[JLeising]

If you are really supplying that much charge current, you could use a lot less resistance to achieve the required voltage drop while dissipating less power in the resistor. Maybe something like this 0.02 ohm resistor (.02 ohms at 50 amps would drop 1 volt and 50 watts in the resistor):
https://www.amazon.com/Current-Sense...+watt+resistor

Good luck -

[jjkd]

How about a high power diode instead? Something like this maybe?

https://www.amazon.com/Amp-Volt-Stud.../dp/B004FGPUE6

That should get you a relatively constant voltage drop of about 0.7 volts regardless of current, unlike using a resistor. Don't forget a decent heatsink, as you could be dissipating up to 35 watts.

[JLeising]

Originally Posted by jjkd

how about a high power diode instead? Something like this maybe?

https://www.amazon.com/amp-volt-stud.../dp/b004fgpue6

that should get you a relatively constant voltage drop of about 0.7 volts regardless of current, unlike using a resistor. Don't forget a decent heatsink, as you could be dissipating up to 35 watts.

excellent suggestion!

[TitanMike]

Originally Posted by jjkd

How about a high power diode instead? Something like this maybe?

https://www.amazon.com/Amp-Volt-Stud.../dp/B004FGPUE6

That should get you a relatively constant voltage drop of about 0.7 volts regardless of current, unlike using a resistor. Don't forget a decent heatsink, as you could be dissipating up to 35 watts.

I think the diode solution would be perfect. However rather than just purchasing a bare diode I'd consider one mounted in a heat sink like this

https://www.amazon.com/Cole-Hersee-4...ttery+isolator

Don't have to use the second connection unless you have a second battery with the same issue.

[Flintstone]

Originally Posted by TitanMike

I think the diode solution would be perfect. However rather than just purchasing a bare diode I'd consider one mounted in a heat sink like this

https://www.amazon.com/Cole-Hersee-4...ttery+isolator

Don't have to use the second connection unless you have a second battery with the same issue.

I appreciate you guys’ thoughts, really I do.

My best-case outcome here would be ;

A. Something that’s tested, proven
B. Something practical and elegantish, in a Forest River sort of way, when this is over, I’d like to try to sell them on the idea of sending out a bunch like it, to fix an oversight they didn’t know they had
C. Or, to prove me all wet, aberrant (that’s actually my first choice)

I have added several batteries, a couple of baked potatoes worth of solar PV and 1/3 the refrigerator requirement,so i get by, at least if I don’t travel an night, it’s not really even about me anymore

[Flintstone]

Originally Posted by Flintstone

I appreciate you guys’ thoughts, really I do.

My best-case outcome here would be ;

A. Something that’s tested, proven
B. Something practical and elegantish, in a Forest River sort of way, when this is over, I’d like to try to sell them on the idea of sending out a bunch like it, to fix an oversight they didn’t know they had
C. Or, to prove me all wet, aberrant (that’s actually my first choice)

I have added several batteries, a couple of baked potatoes worth of solar PV and 1/3 the refrigerator requirement,so i get by, at least if I don’t travel an night, it’s not really even about me anymore

The Sterling BB1260 worked for a while @50% output, before it fried an egg and went loudly to sleep.
The Victron Buck Boost has variable current, 0-50A, I think that’s going to be the answer, I’d like people to know