Battery storage is a technology that allows electrical energy to be temporarily stored in batteries for later use. Below is an overview of how this process works:

Charging

During charging, surplus electricity, for example, generated by solar panels, is converted into chemical energy and stored in the battery cells. This usually occurs when:

• Electricity production is higher than consumption.

• The power grid offers cheap electricity, for example, during off-peak hours.

Storage

The chemical energy is safely stored in the battery cells until it is needed. The storage capacity (usually expressed in kilowatt-hours, kWh) determines how much energy the battery can hold. Modern batteries generally have high energy efficiency, resulting in minimal losses during storage.

Discharging

When there is a demand for electricity, the battery converts the stored chemical energy back into electrical energy. This usually happens in the following situations:

• During peak consumption or high energy costs.

• When insufficient electricity is produced, for example, at night or on cloudy days.

• During power outages, if the battery is part of an emergency power system.

Usage

The released electrical energy can be used to power appliances, lighting, heating, cooling, or other electrical applications in a home or building.

Energy Management

An energy management system (EMS) controls the charging and discharging of the battery. The system:

• Ensures the battery is used efficiently.

• Optimizes lifespan by preventing overloading or deep discharging.

• Can connect with smart meters to manage energy requirements and costs.

Types of Battery Technology

The operation of battery storage partly depends on the technology used. Common types of batteries are:

• Lithium-ion: High efficiency, long lifespan, and compact. Ideal for homes and businesses.

• Lead-acid: Cheaper but less efficient and shorter lifespan. Often used in emergency power systems.

• Flow batteries: Suitable for large-scale applications due to their flexibility and long lifespan.

Frequently Asked Questions

1. How much energy can a battery store?
   The storage capacity of a battery is expressed in kilowatt-hours (kWh). This varies depending on the type and size of the battery, with capacities ranging from 5 kWh to more than 20 kWh for home use.

2. Is energy lost during storage in a battery?
   Modern batteries have high energy efficiency, but typically 5-10% of energy is lost during charging and discharging.

3. What is the difference between lithium-ion and lead-acid batteries?
   Lithium-ion batteries offer higher efficiency, longer lifespan, and compact size, but are more expensive. Lead-acid batteries are cheaper but less efficient and have a shorter lifespan.

Battery storage works by converting electricity into chemical energy, temporarily storing it in, for example, a home battery and later converting it back into usable electricity when needed. An energy management system optimizes this process, making the battery not only work more efficiently but also last longer. Depending on the technology and application, battery storage can contribute to cost savings, energy independence, and more sustainable energy use.