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Victron MPPT charge controllers are among the best solar controllers for charging lithium and lead-acid batteries. In fact, they can be set manually to charge any battery chemistry. While many charge controller settings are straightforward, some require specific expertise to maximize performance.
By the time you finish reading this guide, this post should equip you with the knowledge to take the best out of your solar power system. Proper charging parameters ensure the longevity of your valuable battery bank. Additionally, our guide delves into practical accessories that can enhance your system’s overall performance. This and more info you can find while browsing through the guide.
If you require assistance choosing the most suitable option, we encourage you to explore our recent post on the Best 2023 MPPT Charge Controller.
The above-listed Victron models are only compatible with 12 and 24V battery banks. Make sure to verify the charge controller operation voltage before purchasing a controller.
This manual will guide you through programming of Victron MPPT charging settings for both lithium-ion and lead-acid batteries. Furthermore, we include charging settings for non-Victron controllers as well. The example below reflects a 12V battery bank scenario, for the 24 and 48V systems, simply multiply the 12V values by 2 and 4, respectively.
Step 1
Download VictronConnect App from App Store or Google Play Store, and create an account

Step 2
In the “Device List” look for the charge controller. It should say “SmartSolar”, click on the device image.

Step 3
The Bluetooth pop-up window should appear and you will need to type in the pin code. The default pin is 000000 (six zeros with no spaces in between)

Step 4
If the firmware update is available, click on the Update button below. Do not touch your phone while update is in progress.

Step 5
After seeing the main screen, click on the gear symbol on top right corner following by the battery menu

Step 6
After opening the battery setting page, select the appropriate battery voltage (12,24 or 48V).

Step 7
Go to the battery preset menu and select the appropriate type or chemistry

Victron MPPT charging settings are easy to follow. However, for those who are looking to setup the charging settings manually, the table below is a great source of truth. Also, you can use these settings while programming other charge controllers.
Setting | Lithium-ion battery 12V/24V/48V | Lead-acid AGM, GEL 12V/24V/48V | Lead-acid flooded 12V/24V/48V |
Bulk/Absorption Voltage | 14.4/28.8/57.6V | 14.7/29.4/58.8V | 14.8/29.6/59.2V |
Bulk/Absorption Time | 30 min per 100Ah of LiFePO4 battery | 0.42 x Capacity / Charging Current (e.g. 0.42 * 300Ah / 30A = 4.2 hours | 0.42 x Capacity / Charging Current (e.g. 0.42 * 400Ah / 50A = 3.4 hours |
Float Voltage | 13.5/27/54V | 13.6/27.2/54.6V | 13.5/27/54V |
Equalization voltage Equalization Time | ![]() | 14.7/29.4/58.8V | 15.8/31.6/63.2V 2.5 hours |
Temperature Compensation | ![]() | -4mV/°C/cell | -4mV/°C/cell |
Low Temperature cut-off | 3° degrees Celsius | ![]() | ![]() |
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Overall, adjusting up the battery voltage is the initial step in setting up the system. It’s important to properly maintain the batteries to increase their lifespan and keep them functioning well.
Lithium-ion/LiFePO4
Lithium-ion batteries such as Universal 12V LiFePO4 or a well-known Renogy 12V Lithium have a relatively low self-discharge rate, meaning they lose charge at a slower rate when not in use. However, it is still important to store them in a cool, dry place and avoid overcharging or discharging them too much. In general, avoid discharging a lithium-ion battery below 20% of its capacity to prolong its lifespan and maintain optimal performance. A battery monitor such as BMV-712 Smart Battery Monitor can help extend battery lifespan by providing real-time information and programmable alarms to prevent overcharging, deep discharging, or exposure to extreme temperatures. Additionally, it can also track battery usage and performance over time to identify issues and allow to take corrective actions.
Check Victron Battery Monitor |
Lead-acid
Lead-acid batteries, which are also commonly used in backup power systems, have a higher self-discharge rate. They should be stored in a cool, dry place and kept at a full charge if they will not be used for an extended period of time. It is also important to check the water level in the battery and add distilled water as needed. A battery hydrometer is a tool used to measure the health and charge level of a lead-acid battery. It works by measuring the concentration of sulfuric acid in the battery’s electrolyte, which can help diagnose issues such as overcharging, undercharging, or cell damage that may shorten the battery’s lifespan. Therefore, by using a battery hydrometer to check the health of your lead-acid battery, you can ensure that it is working at its best and potentially extend its lifespan.
Check battery hydrometer |
The Swiss-made “HydroVolt” from Compaselect – a reliable and efficient battery perfect for any off-grid system. What sets this one apart is its built-in temperature compensation, ensuring it can perform optimally in any environment. One crucial factor to consider regarding batteries is the specific gravity. This is the ratio of the density of a substance to the density of a reference substance, typically water. In the case of batteries, it is a measure of the electrolyte’s state of charge. The full specific gravity values of 1.265 for the HydroVolt ensure that you have a battery capable of delivering consistent and reliable performance.
By applying a controlled overcharge, you can ensure that all cells are brought up to the same state of charge. However, over time, the cells of a battery bank can tend to drift apart, causing some cells to become overcharged and others to become undercharged. That’s when you need to equalize the battery bank.
Setting up the charge controller to auto-equalize once in 3 months is essential to ensure that your battery bank is always in top condition. This will help maintain your batteries’ health and ensure that they last for as long as possible.
Lastly, unless your batteries are within a relatively stable temperature environment throughout the year, using a temperature sensor is important. Install the sensor on one of the batteries. It will measure the temperature and send this data to a charge controller. Considering the temperature compensation factor, the charge controller will adjust the charging current based on this temperature data. The two temperature sensors listed below can facilitate this process. By doing so, you can ensure that your batteries receive optimal charging regardless of external temperature variations.
Check Smart Battery Sens | Check Temperature Sensor |
Keep you expensive lead-acid batteries Safe and Clean! Once you’ve given your battery terminals a good cleaning, make sure to apply some battery protecting coating or battery terminal cover kit. Apply a nice, thick layer to keep corrosion away in the future.
May the solar power be with you!
Hey, have you checked out the latest Sunnywell posts yet? By the way, if you haven’t already, make sure you don’t miss out on some of their other amazing content too!
I have just tried putting in details of the batteries I have used on my vehicle and cannot find a closer answer , if the batteries are standard vehicle lead acid , 12 volt ( connected together to give 24 volt ) what setting do I chose on the victron inverter ? It doesn’t have an option for Lead acid ? What should I select please
Hi Richard, please specify the method you use to configure the battery type on the inverter: through the VictronConnect app using Bluetooth, a USB-connected computer with a VE.Direct to USB interface or a Rotary Switch. Choose the GEL/AGM option in the “battery preset” unless you prefer to use a custom charging setting. Please provide the “Ah” size of your battery bank and inverter for us to create tailored settings.
Hello. I have installed a Victron mppt 75/15 and I am trying to make the configuration for this AGM battery
https://www.autobatterienbilliger.at/ective-dc-150-agm-deep-cycle-150ah-versorgungsbatterie
Should I select on the preset the AGM spiral option ?
Thanks for your help
Hi there, using the preset Gel Victron deep discharge(2) would be preferable since its charging settings closely align with the recommended profile for average AGM batteries. The AGM spiral option, on the other hand, has a higher charging voltage that poses a risk of damaging the battery in the long run. Regards, SunnyWell Energy tech
I have a 120AHr Lithium battery in my Ute canopy. The BMS keeps defaulting back to 100% SOC even when the voltage is low. Mostly this happens when we have locked or unlocked the vehicle. What settings can I use to stop this happening?
Hello Suzanne, thanks for reaching out. Are you using Victron battery monitor such as BMV-712? In that case, you need to check your “Charged Voltage” and “Tail Current” settings: they should be 14.1v and 4% accordingly. Cheers,
Hi, I have a 295w solar panel going to a victron 100/30 mppt solar charger and 2x 130ah 12v calcium lead acid batterys, what preset option do I use on the victron app? I’ve set it on gel2 will that be OK? Thanks?
Hello Craig,
Thanks for reaching out. The Gel2 pre-configured voltages look fine except for the float voltage, which is slightly higher than recommended. It should be set at 13.1V instead of a preset 13.8v. Keeping the calcium lead acid batteries at levels can over-charge them. We recommend using the user-defined settings with the following voltages: Absorption voltage = 14.2V; Float voltage = 13.1; Equalize voltage = 16.1V. You can also manually start battery equalization every 2-3 months in summer and more frequently in winter.
Regards,
SunnyWell Energy Tech