Understanding the Mastervolt Lithium Battery System
Article Objective:
In this article, you will get to know the components that make up the Mastervolt Lithium system in your van: what they do, what their potential limitations are, and how to maintain/store the system if not being used for long intervals.
Affected Units:
Vandoit vans with the Mastervolt Lithium system
What components make up the Mastervolt Lithium system?
The lithium system in your van does not solely include the batteries, but the entire Mastervolt management system. The components in the Mastervolt system in your van are:
1. Mastervolt CombiMaster 120 volt series
2. ML-RBS Remote Battery Switch
3. Mac Plus DC to DC Charger
4. Lithium Battery Series: MLI Ultra 12 volt series
5. Mastervolt EasyView 5 or Czone Touch 7 Display
The CZone or MasterBus communication included in the Mastervolt system allows complete system integration, to ensure the best possible recharging, while maximizing the lifetime of your battery.
What does each component do?
1. The CombiMaster is a 3-in-1 combination inverter and charge controller. The inverter part of the CombiMaster converts incoming DC current to AC current that powers many of the van's devices--namely, those devices plugged into the van's 120 volt wall outlets. The CombiMaster has an AC transfer switch, which allows the AC-powered devices to be powered directly from shore power when it is plugged in, as opposed to inverting the battery power. The charge controller part of the CombiMaster detects when shore power has been plugged in and sends any surplus power--that is, charge not being used to power the 120 volt wall outlets (and thus the devices plugged into them)--to charge the batteries. If shore power is unplugged, the charge controller switches back to inverting power. The amount of available inverting power depends on the Combimaster model installed in your van. Look at the front of the Combimaster to determine whether your van can invert 1500, 2000, 3000, or 3500 watts.
2. Each battery has a dedicated ML-RBS Remote Battery Switch is a relay that controls the flow of power in and out of the battery as well as a dedicated fuse for individual protection. This is the big yellow tear-shaped switch in your power box (the number of RBSs you have will correspond to the number of batteries in your system). The top of the switch will automatically depress to enable the battery to receive and distribute power. The top of the switch will automatically pop up if the battery voltage is getting low, the temperature is getting too cold, or an internal system fault occurs. These automated movements preserve battery health. There are "events" scheduled in your battery system to connect or disconnect the flow of power. For example, in the "event" that the battery power gets low, the relay will disconnect to protect the remaining power left in the batteries. Starting the vehicle is an "event" that connects the relay again. If you have questions or concerns about the RBS switch(es) in your van, please contact the Vandoit Customer Support team.
Please note: If your van has the MLI Ultra 12/1250 battery, it has a built-in RBS. Thus, you will not see this yellow tear-shaped switch in your system.
3. The Mac Plus is the device that regulates the charge to your battery/ies from the Ford van alternator at a rate up to 50 amps per device. Vans can be equipped with up to three Mac Plus devices for a total charging capacity of up to 150 amps.
4. Lithium Battery/ies: Depending on the model of your van and the number of batteries installed, battery capacity ranges from 300 amp hours to 1,380 amp hours. The batteries have built-in battery management software that helps maintain a healthy battery system. Vandoit can remotely connect and check on the health and condition of the batteries and make updates as needed. Depending on the battery model, Mastervolt lithium batteries are rated at 3500 cycles down to 80% depth of discharge. For comparison, AGM batteries are typically rated at 500 cycles down to 50% depth of discharge. The lithium batteries can perform under harsh conditions, such as high charge and discharge currents, wet environments, mechanical shocks, or vibrations. The lithium battery receives a charge from shore power, the Ford van alternator, and/or solar panels; stores that charge; and discharges power to the devices in the van. These batteries are built to perform under harsh conditions and withstand the movement and vibrations of the van. The battery comes in a sturdy, waterproof housing.
LIV batteries
DO battery
MOOV batteries
5. The Mastervolt EasyView 5 or Czone Touch 7 is the display screen above the passenger sliding door that controls the Mastervolt system. The waterproof touchscreen allows you to monitor the components of your Mastervolt system and adjust parameters as needed. The display is where you will receive any alerts about the health of your system.
What are the limitations of the system?
One important limitation to be aware of is the operating temperature of each component:
CombiMaster: 14°F to 140°F
ML-RBS Remote Battery Switch: 14°F to 140°F
Mac Plus: -4°F to 140°F
MLI Ultra Lithium Battery: -13° to 122°F
EasyView 5: -4°F to 158°F
Czone Touch 7 Display Screen: -4° F to 158° F
Czone Keypads: -5° F to 131° F
Note that because the CombiMaster may not operate properly below 14°F, your van will not be able to charge via shore power (which gives the impression that batteries may be damaged, but this should not be the case), the Mastervolt control screen may go blank, and AC power will not work.
Also, depending on what charge cycle the batteries are in, attempting a charge below 23°F may result in batteries not accepting charge current, but this does not mean the batteries are not operational or are in danger of damage. The batteries are safe as long as they are above -13°F.
However, the primary battle you are fighting, so to speak, is with battery discharge, not with cold. Keeping your batteries at a high charge is key in all situations. It is important with all setups and temperatures (hot or cold), to eliminate loads from both DC- and AC-powered devices, as this eliminates power draw from the batteries. Higher power draw increases the use of battery cycles, which decreases the life of the battery. In summary, keeping your batteries fully or nearly fully charged and limiting power loads helps in all scenarios, not just cold temperatures.
Another limitation is the sensitivity of the EasyView 5 screen. See this article for more information.
Lastly, it is helpful to know that if the yellow ML-RBS switch is accidentally put into the LOCK OFF/disabled position (point rotated counter-clockwise, top popped up), the inverter will not be able to provide power to the devices in the van unless the van is plugged into shore power or the vehicle is turned on. The switch will need to be manually turned clockwise in order for the system to resume functioning. Starting the vehicle or plugging the van into shore power will trigger the system to re-engage and resume charging.
Maintaining/Storing the Mastervolt System if Not Being Used for Long Intervals
If your van is equipped with the Rear Battery Disconnect Switch, charge the batteries to 100% and turn the switch to off to store the batteries during periods of non-use. If your van is not equipped with this Switch, follow the guidelines below.
If your van will be unused for more than 2 days, or if you are putting the van into long-term storage, please follow these two sets of guidelines:
Van Unused 2 Days - 2 Weeks:
1. Keep the van plugged into shore power.
2. Every 2-3 days, check the battery level:
On the first page of the EasyView 5 monitor, look for the square that displays a percentage for the "Primary State of Charge."
On the main page of the Touch7 monitor, look for the icons for "TOP BATTERY REMAINING" and "BATTERY CHARGED." Tap on these icons to reveal more battery data.
The lowest amperage draw you can expect to observe will be -1.0 to -2.0 amps. This can be accomplished when all electrical devices are unplugged and the inverter is turned off.
Depending on when you received you van, the monitor layouts may look different. If you cannot locate the correct data square/icon, contact Vandoit Customer Support.
Van Unused Longer Than 2 Weeks:
1. Plug the van into shore power and charge the battery bank to 100%.
2. Leave the battery/ies installed in the van; there is no need to remove them.
3. Turn the yellow RBS switches to the locked position; the word LOCKED is imprinted on the top of the black housing of the RBS.
4. Turn off all circuit breakers. In the DO model, the circuit breaker panel is located on the power tower. In the LIV model, it is located on the front of the power box, behind where a 2-seat bench or kitchen pod may be installed in your van.
LIV circuit breaker location:
5. As often as is reasonable, check the battery level using step 2 above.
Note: Mastervolt batteries' rate of self-discharge is less than 5% per month. Low ambient temperature affects the self-discharge rate of the batteries. Keeping batteries charged above 60% is key to their health.
To resume using your van after long-term non-use/storage:
1. Turn on all of the circuit breakers.
2. Turn the yellow RBS switches to the unlocked position.
3. Drive the van for at least 1 hour and then plug it into shore power. Driving will automatically press the top of the yellow switch(es) in to begin charging the battery. After long-term storage, we always recommend charging the battery all the way back up to 100% from either driving the vehicle or charging from shore power.
4. After 1 day of being plugged into shore power, use the Mastervolt lithium monitor to check the battery level. If it is lower than 80%, please reach out to the Vandoit Customer Support team by submitting a ticket through the Customer Support portal or emailing support@vandoit.com. Please include photos of each page of the Mastervolt screen.
Do you have additional questions about your lithium system?
Be sure to read other articles in the Vandoit Knowledge Base library about the lithium system. If these articles do not provide the answers you are looking for, please submit a ticket through the Customer Support portal or email support@vandoit.com.
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