Victron MPPT LiFePO4 Settings: How to Program It

The right Victron MPPT LiFePO4 settings come up in nearly every comment section under Victron solar videos. People ask about absorption, float and how long to hold them. Victron’s MPPT manual gives default lithium values, and your battery maker may give others. Here’s how to set them in VictronConnect and what each value means.

A walkthrough of lithium settings on a Victron MPPT.

Electrical work can be dangerous: follow the manual, fuse and size every cable correctly, and use a licensed electrician for anything connected to household wiring.

Victron MPPT LiFePO4 Settings (Victron Defaults)

Setting	12V system	24V system
Absorption voltage	14.2V	28.4V
Absorption time	2h	2h
Float voltage	13.2V	26.4V
Equalisation	Not available for lithium	Not available
Temperature compensation	0mV/°C (off)	0mV/°C

Source: Victron MPPT solar charger manual, “Lithium batteries”. Victron notes that LiFePO4 doesn’t need to be fully charged to prevent premature failure. These values are adjustable.

For reference, Victron’s own Lithium Battery Smart datasheet calls for 14.0–14.4V charge (14.2V recommended) and 13.5V float on 12V. Always use your battery maker’s values when they differ.

Step-by-Step in VictronConnect

Update the controller firmware first.
Open Settings > Battery and set the battery voltage manually (12V, 24V or 48V) instead of leaving it on auto.
Set Max charge current to your battery’s recommended charge rate.
Under Battery preset, pick the built-in LiFePO4 preset or create a user-defined one.
To change individual values, turn on Expert mode. This unlocks bulk, absorption and float voltages, the re-bulk offset, absorption time and tail current, and low-temperature cut-off.
Set the low-temperature cut-off to match your battery’s minimum charge temperature. Victron’s own lithium batteries charge from +5°C.
Save the preset so you can load it on your other Victron chargers.

Common Mistakes

Different chargers, different voltages. If an inverter-charger or DC-DC charger is set higher than the MPPT, the MPPT can throw PV-input shutdown errors (38/39, 80–88).
Leaving temperature compensation on. That’s a lead-acid feature, and lithium uses 0mV/°C.
Ignoring the BMS. With a managed battery and a GX device, DVCC can take over charge voltage and current, and the controller then shows “externally controlled”.
Expecting 100% every day. A short 2-hour absorption is normal for LiFePO4.

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Victron’s SmartSolar MPPT 100/30 page has the datasheet and manual, or you can check the SmartSolar 100/30 on Amazon.

Worked Example: Matching the MPPT to a 12V 200Ah LiFePO4 Battery

Say the battery maker recommends 14.2–14.4V charge, 13.5V float and a maximum charge current of 100A, and you have a SmartSolar 100/30.

Battery voltage: set manually to 12V.
Max charge current: leave at 30A. It’s well below the battery’s 100A limit.
Absorption: 14.2V, which sits inside the maker’s range.
Float: 13.5V if the maker specifies it; Victron’s lithium preset uses 13.2V, and either keeps the battery topped up.
Absorption time: fixed at 2h, the lithium default.
Low-temperature cut-off: set to the battery’s minimum charge temperature, for example 5°C.

Example values; always use your own battery’s datasheet.

Worked Example: The Same Bank on 24V

On a 24V LiFePO4 bank, double the 12V values: absorption 28.4V and float 26.4V in Victron’s lithium preset, or 27.0V float if your battery maker specifies 13.5V per 12V block. Max charge current on a 150/35 would be 35A, again below a typical 24V 200Ah battery’s limit.

What the Expert Mode Settings Do

Re-bulk voltage offset: how far the voltage must fall below float before a new charge cycle starts. A larger offset means fewer cycles for a LiFePO4 bank that’s mostly sitting full.
Tail current: ends absorption early once charge current drops below this level, so the controller moves to float sooner when the battery is full.
Adaptive absorption time: a lead-acid feature that scales absorption time with how deeply the battery was discharged. A fixed time suits lithium.
Low-temperature cut-off: stops charging below the set temperature. Victron’s lithium preset sets 5°C; it needs a temperature reading, such as from a Smart Battery Sense or SmartShunt with a temperature sensor.

Keeping Every Charger on the Same Values

In a system with an MPPT, a DC-DC charger and an inverter-charger, set all three to the same absorption and float voltages. Victron’s VE.Smart Networking lets compatible chargers share voltage, temperature and current readings over Bluetooth, which keeps them working together. With a GX device and a managed battery, DVCC does the coordination for you.

Checking the Result

After a sunny day, open the History tab in VictronConnect. Each day shows time in bulk, absorption and float, plus the maximum battery voltage and the energy harvested. A day that reaches float after about two hours of absorption shows the settings are working as intended.

When the Battery Has Its Own Bluetooth BMS

Many third-party LiFePO4 batteries include an internal BMS with its own app. The MPPT doesn’t talk to it directly, so the controller’s voltages need to sit comfortably inside the BMS limits. Setting absorption a little below the BMS’s high-voltage cut-off means the charger, not the BMS, ends the charge, which is gentler on the system. If the BMS app shows cell voltages, a look at them near the end of absorption confirms the cells are charging evenly.

Saving and Sharing Presets

VictronConnect lets you save a user-defined battery preset and load it on other Victron chargers, such as a second MPPT or an Orion XS. That’s the quickest way to keep every charger on identical values, and it makes it easy to restore your settings after a firmware update.

FAQ

Should float be 13.5V or 13.2V?

Victron’s MPPT default is 13.2V, and its Lithium Smart battery datasheet says 13.5V. Follow your battery’s datasheet.

Do I need a battery temperature sensor?

For cold climates, yes. Use a Smart Battery Sense or a SmartShunt with a temperature sensor over VE.Smart Networking.

Can I use the “Smart Lithium” preset with any LiFePO4 battery?

It’s a reasonable starting point, but check the absorption and float values against your battery maker’s datasheet and adjust them if they differ.

Should I set a tail current for lithium?

Many owners use one so absorption ends once the battery is full; your battery maker’s recommended end-of-charge current is a good value to use.

Sources: Victron MPPT solar charger manual (“Lithium batteries”, “Battery settings”, “Expert mode”, troubleshooting) and Lithium Battery Smart datasheet (victronenergy.com, accessed Oct 2026).