Victron Lithium Battery System Upgrade

Upgrade your vessel electrical system with Victron Smart Lithium batteries and associated equipment. This application note shows a typical Schematic Diagram and Bill of Materials for a high-performance Victron based Lithium system.

With large battery capacity and sufficient solar power generation, the system provides all of the electrical power requirement without the need for a generator. In cases where a generator is available, Genset run-time is significantly reduced as it charges the battery at peak efficiency.

Following is a system that can run 240-volt AC electrical equipment including cooking and air conditioning, 

  • 5,000VA Quattro inverter charger for all 240-volt electrical power
  • 1,000-watt solar panel array
  • Cross charging from vessel engines

The system shown is for a dual-engine 12-volt vessel. Variants for 24-volt batteries and single-engine vessels are readily adapted.

Victron Smart Lithium batteries are not limited in charge and discharge current by an internal BMS. Each cell has a balancing module and a communications circuit that can signal external circuitry when an abnormal voltage or temperature situation is met. The external BMS will signal load and charge devices to disconnect from the battery as required.

Other external BMS systems take a brute force approach by switching the battery in and out of the circuit. For instance, a low voltage condition would disconnect the battery entirely whereas the Victron system would only disconnect the load circuits and leave the charge circuit path available.

This system is desirable when employing large amp-hour capacity systems that can expect a high charge and discharge current.

The diagram shows the essential Victron components required for a VE.Bus inverter charger system. Outback Marine provides detailed schematics and functional diagrams for specific designs.

Equipment List

12-volt House Battery Bank
The batteries are connected in parallel to make a 600 amp-hour 12-volt battery bank. A continuous charge and discharge rate up to 300-amps (.5 x C-rate) is available. Short term discharge current in excess of 2 x C-rate is possible.
The Battery Management System communicates battery status to all charge and discharge circuits to protect the battery from over-voltage, under-voltage and high-temperature conditions. 
DC Distribution Board
The DCDM2 provides a battery switch and fused bus bar system for all heavy DC circuits. An unswitched fuse provides power for 24-hour circuits. Each positive feed has a mounting position for an  MRBF Terminal Fuse. A  Victron BMV-series current shunt mounting provision is made on the negative busbar.
Cross Charge Device
A Cyrix-Li charge relay connects the vessel engine charging system to the house battery when the engine is running. A charge disconnect signal from the VE.Bus BMS will disable this function for an abnormal battery condition. One is fitted for each engine.

Solar Panels

The solar panel capacity is limited by the available space on the vessel. In this case, four 285-watt panels should yield around 400 amp-hours of charging on a good day.
Solar Controller
Four 285-watt panels have an effe3ctive charge capability of 66.5-amps at peak midday (4 x 285 X.7 /12). The 150/60 controller is adequate for the job. Alternatively, two 100/30 controllers could be used where each controller services two panels.
Solar Remote Control
The BMS requires control of all charge sources. The VE.Direct remote cable connected to the solar controller VE.Direct port will disable this solar charging for an abnormal battery condition. One cable is required for each solar controller in the system.
House DC Circuits
Custom Circuit Breaker Panels
Vessel house circuits are generally driven from a circuit breaker panel. The battery switch controls all circuits connected to the load side of the battery switch. Some circuits such as solar charging, bilge pumps and vessel security require a 24-hour power feed that is independent of the battery switch.
House Battery Protect
The Battery Protect controls power supplied to the House DC Circuits. The VE.Bus BMS can turn the power off if a low battery voltage condition persists. Select the size of the Battery Protect to exceed the maximum simultaneous DC load on the house circuits.
24-Hour Battery Protect
The VE.Bus BMS can turn the power off if a low battery voltage condition persists. Select the size of the Battery Protect to exceed the maximum simultaneous DC load on the 24-hour circuits.
Inverter Charger
The Quattro Inverter Charger is suited for vessels that are fitted with a generator. Otherwise, use a Multiplus. A VE.Bus cable connects to the VE.Bus BMS to control the battery charger and inverter load switching for abnormal battery conditions. The inverter charger will require special programming for compatibility with the lithium system.
Digital Remote
Provides remote control of the Quattro inverter charger. 


System Configuration

The final system design depends on a number of factors including the use case of the vessel and existing equipment. Outback Marine can provide a System Configuration that will meet individual needs. It includes an equipment layout, circuit panel design and detail bill of materials. Contact us for more detail.