Tow Vehicle Alternator Charger Kit (Drop-In Lithium)


Tow Vehicle Alternator Charger Kit (Drop-In Lithium)


Enable 120A alternator charging of a drop-in lithium battery bank from a tow vehicle.  This kit is ideal for trailers and fifth wheels.

Add To Cart

With most tow vehicles and trailers, the seven pin connector allows alternator charging of the trailer’s battery bank. The trailer's seven-pin connector is typically hardwired leaving the tow vehicle responsible for charging the two battery systems. Unfortunately, many vehicles don't have any protection built in, which leaves both battery banks tied together when the trailer plugged in. This is a major concern for lithium house batteries as their resting voltage is much higher than a typical tow vehicle engine battery. This causes the lithium battery to slowly discharge into the tow vehicle battery and because lead-acid batteries can dissipate energy in the form of heat, this will continue to happen until the lithium battery is below 20%, which could potentially cause damage to the lithium battery. This isn't good for the system, and can be avoided by installing this kit or simply unplugging the trailer when left for more than a week. In addition to protecting both your trailer and tow vehicle's electrical systems, the Cyrix-Li-Ct Isolator allows for bi-directional charging if your vehicle allows it. This means that if you have a solar charger, or a shore power connection, the lithium battery system may be able to maintain the tow vehicle’s starter battery in a way that doesn’t jeopardize the health of either battery system.

Wiring Diagram

What you get:

1x RELAY-VTC120 CYR010120412 (Li 120A) Cyrix-Li-ct 12/24V-120A Intelligent Li-ion battery combiner
1x SPLICE-14-SWL P2-HEX 2-14 ga. Splice Wire Lug
3" HS-BLK-DWALL-3/4 Heat Shrink 3/4" Black
2x LUG-18GA-FAST-F 30513 Female Fast-on 18 ga.
2x LUG-6GA-RING-1/4 6 ga. Lug-1/4” Ring
1x 93B-030A 30 Amp DC Brkr. w/Screws
1x SPLICE-14-BUTT-SD 14-16 ga. Butt Step-Down
1x LUG-10GA-RING-HS 10-12 ga. Ring-H.S.
1x FUSEHLDR-MINI Mini Fuse Holder & Cap
2x FUSE-MINI-002A Mini Fuse-2 Amp
5' CABLE-18GA-1-BLK 18 ga. Black Wire
1' CABLE-18GA-1-RED 18 ga. Red Wire
1x LUG-18GA-RING-BR 30006 18-22 ga. Ring-Bare
2" HS-BLK-DWALL-1/2 HSDW38-0 Heat Shrink 1/2" Black
5" HS-RED-DWALL-1/2 Heat Shrink 1/2" Red (2x 1/2" pieces)
7' CABLE-6GA-1-BLK Wire-6 ga.
5x LUG-6GA-RING-3/8 6 ga. Lug-3/8" Ring


AM Solar Part Number:  98-ALTCLITOW