Advice for simple lithium system - Page 2

larrie · 11-20-2021, 09:49 PM

You should check the recommended charging rate for the battery you are getting. For example, my 100 AH SOK battery has a recommended charging rate of 20 amps so that is what I have the Kisae DMT1250 set at. I have run it higher, 35 amps, although from what I have seen you should follow the manufacturers recommended charging rate to prolong the life of the battery.

Scalf77 · 11-21-2021, 06:10 AM

Larrie,
Good point about spec of the battery. That is another plus of being able to set charge rate like the KISAE can do.

I will say that I am surprised that the SOK battery has recommended rate of 20 amps. Max charge rate for the Battleborn 100 amp is 50 amps.

-greg

86Scotty · 11-21-2021, 07:15 AM

Interesting, I did not know that about lithium batteries. I haven't decided on a battery, or any of this, quite yet. Thanks everyone, good intel.

Scalf77 · 11-21-2021, 08:00 AM

Actually all batteries have a max charge rate, lithium is generally higher than AGM, which can be higher the wet cells. The bigger difference in lithium is the internal BMS (or external) will have a limitation on battery discharge rate.

-greg

Lilnuts2 · 11-23-2021, 10:40 AM

With the Renogy DC to DC like in Will's video. What if your chassis battery is a flooded type and your house is a lithium The charger is set for lithium. The van is parked and the solar/Lithium is trickle charging the chassis battery, is it using the Lithium charge profile for the flooded battery?

86Scotty · 11-23-2021, 12:34 PM

Great question.

larrie · 11-23-2021, 09:33 PM

Another question I have about the Renogy is how it keeps from sucking all the power out of the starter battery when the vehicle is off? The Kisae charger has a key switched sensing wire that tells it when the car is running. I do not see this on the Renogy.

Scalf77 · 11-24-2021, 05:57 AM

So I am not really sure about Lithium house to wet cell starter, all documentation says that when it is float it will combine for 1 min and check voltage and repeat process while you are in float and the house is charged. Their lithium profile doesn't have a float stage, so I guess that means it doesn't.

That said you could do a custom profile, as many Battleborn being one that support a float stage, this would probably allow it to work. They internally cut off the input to the alternator section, they do have an ignition wire, which is there to configure the unit to work with a smart alternator. The standard alternator setting will kick in at 13.2 volts for 15 secs. It is possible that they have a solar only mode also, their docs don't spend a lot of time on this feature.

And to be clear although listed at 50 amps. it is 25 from alternator and 25 from solar for a max of 50. Still not a bad set up, they also have sense lines for the output voltage, which can add to the accuracy of the output, a nice feature.

Larrie,
The ignition input for the Kisea is also their to determine if your sensing voltage for standard alternator or smart alternator. You do not need it wired for your E-series.

I have installed an 80-amp relay on the input of the Kisea that was controlled by "run" circuit to isolate the input of the Kisea when not running. This is actually harder to tap into that circuit on a E-series, for a Transit there is a connection under the driver seat.

-greg