Home » BIM and Energy » Solar battery installation: tips for an optimal setup

how to install battery to solar panel

Solar battery installation: tips for an optimal setup

Where to install solar panel batteries for maximizing storage and accessing tax deductions

Solar panel batteries are essential for optimizing solar energy usage and increasing the efficiency of existing photovoltaic systems.

By storing the energy produced by solar panels, they allow maximizing self-consumption, reducing dependency on the traditional electrical grid.

To enjoy these benefits, it’s crucial to size the system correctly according to consumption. Thus, utilizing dedicated solar design software can help configure the storage system according to user needs.

What are Solar Panel Batteries?

Solar panel batteries are specialized energy storage systems integrated into installations, allowing the preservation of unused energy for nighttime or low sunlight periods.
A photovoltaic system with storage batteries can be:

  • Off-grid photovoltaic system: Not connected to the national electrical grid but linked to an autonomous energy storage system that stores electricity produced by the system and provides it directly to the user when needed.
Stand alone photovoltaic system

Stand alone photovoltaic system


  • Grid-connected photovoltaic storage system: A system where solar energy produced is initially stored in storage systems, and once the batteries reach their maximum capacity, the residual energy is fed into the national electrical grid. This type of system is also known as a hybrid photovoltaic system, combining storage batteries with grid access.


Grid-connected photovoltaic storage system

Grid-connected photovoltaic storage system

Types of Photovoltaic Batteries and Accumulators

Various types of batteries are used in photovoltaic installations, each with specific characteristics and technologies.
The main categories of accumulators include:

  • Lithium batteries: With higher efficiency and discharge capacity up to 90%, ideal for maximizing energy self-consumption, they are less bulky than lead-acid batteries and have an average lifespan of 10-12 years, but come with a higher price tag;
  • Gel batteries: Known for higher safety and resistance to extreme temperatures, but with lower discharge capacity compared to lithium batteries;
  • Stationary batteries: Known for reliability and durability, ideal for industrial and commercial applications requiring continuous and stable operation;
  • Lead-acid batteries: Among the most common, offering low costs but an average lifespan of 3-5 years and limited discharge capacity of 50-60%;
  • AGM batteries: Similar to lead-acid batteries but with a glass-matrix structure making them more resistant to vibrations and shocks;
  • Nickel batteries: Less common but with higher charge and discharge capacity compared to lead-acid batteries.

Choosing the most suitable battery depends on specific user needs and factors such as capacity, power, and number of charge cycles. It’s advisable to accurately calculate the electrical consumption profile to properly size the accumulator according to the home’s energy needs.

I therefore suggest that you carry out this calculation using special photovoltaic software that allows you to calculate the right battery sizing according to the energy needs of the house and the user.

Battery Lifespan

Regarding lifespan, high-quality storage batteries can offer warranties of up to 10-20 years and are designed to support between 10,000 and 12,000 complete charge cycles. However, the useful life of the batteries can vary depending on the technology used and usage conditions.
The longevity of photovoltaic storage batteries is closely related to the number of charge cycles: the more frequent the charges and discharges, the shorter the lifespan of the storage system.

To keep batteries in optimal conditions over time, it’s crucial to manage them properly, storing them in a dry environment and occasionally protecting them from high temperatures with a suitable cooling system.

Characteristics of Photovoltaic Storage Batteries

Modern photovoltaic storage systems occupy relatively small spaces. For example, a 5 kW system occupies approximately 1 square meter of surface area.
Sizes may vary depending on battery type and storage power but usually remain compact.

Batteries for photovoltaic storage are enclosed in specific casings connected to a ventilation system. These containers are designed to ensure optimal insulation, protecting batteries from temperature variations and reducing the risk of direct contact with people.

How to Install Solar Panel Batteries

For an efficient battery installation, it’s advisable to follow a series of detailed steps:

  • Accurate planning: It’s essential to select the most suitable storage system for one’s needs and the characteristics of the photovoltaic system. Therefore, evaluating battery sizes and capacities and designing a suitable ventilation system to ensure safe and efficient operation is necessary;
  • Financial analysis: Before installing photovoltaics, conducting a thorough analysis of overall profitability, considering amortization, return on investment time, and other relevant financial indicators;
  • Compliance with bureaucratic procedures: Obtaining all necessary authorizations for battery installation is mandatory, ensuring full compliance with current regulations;
  • Installation and technical maintenance: Managing and maintaining the storage system are crucial to ensure optimal performance over time and maximize the energy and economic benefits of the photovoltaic system.

To avoid installation issues, it’s recommended to use a solar design software that guides you through the process, from a financial evaluation with a business plan to activation, sizing, and configuration of the accumulator defining the battery type.

Where to Install Solar Panel Batteries

Choosing the ideal location for installing photovoltaic batteries is crucial to ensure the correct operation and longevity of the storage system over time.
It’s advisable to select a well-ventilated environment protected from temperature fluctuations to provide optimal operating conditions for batteries and reduce the risk of damage or malfunctions caused by external agents. Additionally, safety considerations and compliance with specific regulations to prevent potential explosion or fire risks, ensuring safe installation, are essential.

Outdoor installation is not recommended as weather conditions like rain, snow, and insect intrusion could cause serious damage to the storage system.

The optimal solution is to use an internally protected environment sized according to the volume of photovoltaic batteries, capable of maintaining a stable and controlled temperature throughout the year.

Where to Install Solar Panel Batteries Indoors

The most frequently chosen locations to house photovoltaic batteries are the garage and the basement.
This preference stems from the need for sufficient surface area to support the considerable weight of the storage system. Indeed, the weight of the photovoltaic storage can vary from 60 to 150 kg, depending on battery type and capacity. Therefore, installing storage batteries in the attic is not recommended unless adequate ventilation and a solid support structure are guaranteed.

During normal charging and, especially, in case of overcharging, batteries can release hydrogen and oxygen. Therefore, ensuring adequate air exchange in the surrounding environment is essential to prevent exceeding safety limits.

Finally, choosing a dedicated technical room or a garage/basement also facilitates maintenance and inspection operations, simplifying battery replacement.

Where to Install Outdoor Solar Panel Batteries

If it’s not possible to allocate batteries indoors, the option remains to place them outside the building.
In this case, it’s crucial to protect the storage from weather conditions, insects, and leaves by installing a dedicated cabinet for outdoor photovoltaic batteries.

Installing Batteries on Existing Photovoltaic System

To add storage batteries to an existing photovoltaic system, it’s essential to carefully evaluate the characteristics of both the batteries and the system itself. Sizing batteries appropriately concerning system specifications and user needs is crucial.
Most photovoltaic systems are designed to allow easy and uncomplicated integration of storage batteries. This means that it’s possible to improve the efficiency and autonomy of one’s photovoltaic system without having to replace the entire system.

In case one wishes to integrate batteries into an existing photovoltaic system, it’s advisable to opt for a storage system with the following specifications:

  • AC-side connection;
  • Compatibility with any photovoltaic inverter model;
  • Adaptability for both single-phase and three-phase electrical systems;
  • Presence of an integrated monitoring system.