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Topic: How to not blow up MY Alternator when charging Lithium (Read 2285 times) previous topic - next topic

Re: How to not blow up MY Alternator when charging Lithium

Reply #25 –
Quote from: wolfe10 –
I would NOT upgrade the alternator to a higher-amp unit.

The U225 has the Cummins B engine with 230 HP. Taking a higher HP drain for a larger alternator would not be something I would recommend.

Horsepower to alternator calculation. In theory 746 watt/hours is one horsepower. 100 amps even at 14 volts + 1,400 watts, ~2 HP. Add some extra due to inefficiency of the alternator and diode block. (~75%). As the batteries are charged and the load drops so will the HP requirement. No one will be able to tell if you have a 160- or 200-amp alternator. The parasitic losses from the air compressor, cooling fans, and AC are much worse.
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: How to not blow up MY Alternator when charging Lithium

Reply #26 –

Well, every situation is a little different and for right now I decided to go with a simple $20 DC-to-DC Charger https://www.amazon.com/dp/B07CK2PCC7/ref=pe_386300_440135490_TE_simp_item_image solution and 3 battery banks (lithium, house & starter) which this video describes. Actually I got this for free along with another $40 for signing up for an Amazon Visa card.

https://youtu.be/exQSsTiclOo?si=TOhAEc36FRatIQFO

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: How to not blow up MY Alternator when charging Lithium

Reply #27 –
Quote from: Dakota Slim –
Well, every situation is a little different and for right now I decided to go with a simple $20 DC-to-DC Charger Amazon.com : HUINE 20A 12V 24V Auto IP68 Waterproof PWM Solar Charge... solution and 3 battery banks (lithium, house & starter) which this video describes. Actually I got this for free along with another $40 for signing up for an Amazon Visa card.

https://youtu.be/exQSsTiclOo?si=TOhAEc36FRatIQFO
This is not a battery or alternator to battery charger. This is to connect a solar panel to a battery and a load.
20A into a 300 A/H bank would be a 15-hour charge rate with any load present adding to that charge time.

Dennis
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: How to not blow up MY Alternator when charging Lithium

Reply #28 –
Quote from: Dennis H –
This is not a battery or alternator to battery charger. This is to connect a solar panel to a battery and a load.
20A into a 300 A/H bank would be a 15-hour charge rate with any load present adding to that charge time.

Dennis
Hi Dennis. You apparently didn't watch Tito's video. He has 134,000 YouTube subscribers. The beauty of this hack is I get to keep my existing solar controller, inverter, converter, alternator and isolator plus all the existing wiring and I don't have to worry about damaging my lithium battery or the alternator. 
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: How to not blow up MY Alternator when charging Lithium

Reply #29 –
Quote from: Dakota Slim –
Hi Dennis. You apparently didn't watch Tito's video. He has 134,000 YouTube subscribers. The beauty of this hack is I get to keep my existing solar controller, inverter, converter, alternator and isolator plus all the existing wiring and I don't have to worry about damaging my lithium battery or the alternator.

He is using this as a maintenance charger for the chassis battery using the higher voltage from the house lithium set at rest to charge the chassis lower voltage chassis battery.
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: How to not blow up MY Alternator when charging Lithium

Reply #30 –
Exactly, but I have a 5 amp Trik-L-Start already charging the start battery from my AGM house battery which is currently being charged by the converter and was being charged by my solar panels.
I am adding a lithium battery as a separate bank which will be charged solely by my solar panels via the solar controller. This 20 amp B2B charger will use the lithium battery to help charge the AGM house battery (along with the converter) which uses the Trik-L-Start to keep the starting battery topped off. 
When I go off grid, the lithium battery will also power my inverter.
I intend to put a switch between the lithium battery and the AGM house battery so that when the alternator is running there is no way for it to damage itself or the lithium battery.
That's my plan and I think I'm sticking to it.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird
 

Re: How to not blow up MY Alternator when charging Lithium

Reply #31 –

Update: The Huine charge controller ad didn't mention it but the user manual said it was not suitable for use with lithium batteries. Based on Tito's YouTube video, I hooked it up and it works but after a little more searching I found a $34.85 Victron Energy Orion IP67 24/12-Volt 10 amp DC-DC Converter that is suitable for using a solar charged lithium battery to charge an AGM battery AND it comes with extra long cables.
I also went with a different 20 amp breaker. This one's (2nd link) mount is different and it will reset automatically.

Amazon.com: Victron Energy Orion IP67 24/12-Volt 10 amp DC-DC Converter,...

Amazon.com: 20A DC 12V - 24V- 48V Automatic Reset Circuit Breaker with Cover...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird