Rated capacity (Ah or kWh): How much energy a battery can store

Rated capacity determines how much energy a battery can store and deliver. This is expressed in ampere-hours (Ah) or kilowatt-hours (kWh). The higher the capacity, the longer a battery can provide power before recharging is required.

What does nominal capacity mean in practice?

Ah (ampere-hour) indicates how much current a battery can deliver for a given time. For example, a 100 Ah battery can deliver 10 amps for 10 hours.
kWh (kilowatt-hour) measures the total energy content. A 10 kWh battery can power a 1 kW device for 10 hours.

Why is rated capacity important?

Capacity determines how much energy is available for storage and use. This affects the autonomy of an energy storage system and is crucial when choosing batteries for solar, grid stabilization and peak shaving.

ZMission, supplier of AlphaESS, offers battery solutions optimized for energy needs and efficiency, ensuring maximum storage and reliable energy management.

Voltage & Current: How batteries supply and receive energy

Batteries operate on the basis of voltage and current, two crucial factors that determine how efficiently and safely energy is stored and released. Proper voltage and current values ensure optimal performance and longer life.

Rated Voltage (V)
The rated voltage is the average voltage a battery or cell delivers during use. This gives an indication of how the battery performs under normal conditions.

Charge voltage & discharge voltage
Every battery has a maximum and minimum voltage level within which it can safely operate.

• Charge voltage is the maximum voltage the battery can handle without damage.
• Discharge voltage is the minimum voltage before the battery is fully discharged and needs to be recharged.

Charge current & discharge current (A)
The current rating determines how much energy a battery can deliver or receive while charging and discharging.

• Higher charging currents shorten charging time, but can cause the battery to wear out faster.
• Discharge currents determine how much power is available to devices or energy storage systems.

At ZMission, supplier of AlphaESS, battery systems are designed with proper voltage and current ratings for maximum efficiency, safety and performance in energy storage and management.

Rated and peak power: How much energy a battery can deliver

Batteries deliver energy in kilowatts (kW), with both continuous and peak power determining performance in various applications.

Rated Capacity (kW)
Rated capacity indicates how much energy a battery can deliver or absorb continuously without loss of performance. It determines how well a battery can withstand long-term loading and is essential for applications such as energy storage for businesses and households.

Peak power (kW)
Peak power is the maximum power a battery can deliver for a short period of time, for example, to handle sudden peak loads. This is crucial for situations where high power is needed in a short time, such as when starting heavy machinery or stabilizing a power grid.

ZMission, supplier of AlphaESS, offers battery solutions that deliver both high rated and peak power, making them suitable for power management, peak shaving and grid stabilization.

Environment & Safety: How batteries function optimally and safely

Batteries perform best within controlled conditions. Proper thermal management, protection systems and protection from external factors are essential for safety and long life.

Thermal Management
The Battery Management System (BMS) regulates temperature and ensures that the battery remains within safe limits. This prevents performance degradation and extends battery life.

Thermal runaway
In lithium iron phosphate (LFP) batteries, thermal runaway is not a significant risk due to their stable chemical composition. Batteries from AlphaESS offer additional protection and are equipped with fire and heat-extinguishing fire exhausters for maximum safety.

Self-discharge
Batteries lose a small percentage of energy even when not in use. This self-discharge rate determines how long a battery can hold energy without being recharged.

IP rating
The IP rating indicates the extent to which the battery is protected against dust and water. This is especially relevant in outdoor applications or environments with a lot of moisture and dirt.

BMS (Battery Management System)
The BMS monitors and protects the battery from overcharging, overheating and deep discharge. This system ensures that the battery operates safely and efficiently, regardless of operating conditions.

SOC control and balancing
State of Charge (SOC) control and balancing ensure that all cells in a battery pack are charged and discharged evenly. This prevents performance degradation and extends battery life.

ZMission, supplier of AlphaESS, offers batteries with advanced safety and management systems that ensure optimal performance even under challenging conditions.

PGS 37 Guidelines and Insurability of Battery Storage

The PGS 37 guidelines place strict requirements on the placement of energy storage systems. In short, this means that a battery must be placed outside the building, with a minimum distance of 10 to 15 meters. If this is not possible, structural measures must be taken, such as a separate fireproof room with a fire resistance of at least 60 minutes.

Failure to comply with these guidelines can directly affect fire coverage on homeowners’ insurance policies. In that case, insurers may decide to exclude fire-related damage caused by the battery, posing a significant financial risk.

Example from practice
A company with a solar panel installation wants to add a battery storage system to enable energy storage and peak shaving. Without specific insurance arrangements, PGS 37 requires the battery to be placed outside the building, which results in significant additional costs and loss of space. Moreover, in many cases this is not possible due to dense buildings, too small a site or other spatial constraints.

However, the batteries of ZMission, AlphaESS and AlphaESS Storion are so safe that the fire risk is negligible.
As a result, ZMission was the first battery supplier to realize a unique insurance arrangement: a major Dutch mutual insurer was willing to simply insure these batteries, without additional requirements or premium surcharges.

This allows the AlphaESS and AlphaESS Storion batteries supplied by ZMission to be co-insured under standard policy terms, with no additional surcharges or additional requirements. This means customers benefit from:

Full fire coverage without exclusions within building insurance

• No additional fees or surcharges on the insurance premium
• Flexible placement – indoors or against the facade without restrictionsNo Additional
• Placement Requirements Outside Standard Safety Standards

ZMission, AlphaESS and AlphaESS Storion batteries meet the most stringent international safety and certification standards, including:

• Use of LiFePO4 (LFP) batteries – known for their thermal stability and low flammability
• Multiple security – 3-level software protection and ASIL-D security certification
• Guaranteed longevity and reliability

Thanks to these features, the PGS 37 directive does not apply, and no additional construction measures are required for indoor installation.

Scope 10 Inspection – A Standard Safety Inspection
As with any electrical installation, a Scope 10 inspection is required. This is a general safety inspection for electrical installations and not an additional requirement specific to battery storage.

With ZMission, supplier of AlphaESS and AlphaESS Storion, you choose a safe, insurable and future-proof battery solution, without unnecessary additional costs or placement restrictions.

The C-Value: The speed score of your battery

The C-value determines how fast a battery can charge and discharge relative to its total capacity. A higher C-value means faster energy release and shorter charge times, which is crucial for applications where instant power is needed.

How does the C-value work?
The C-value is expressed as a multiplication of the battery capacity. For example:

• 1C means that a battery with a capacity of 100 Ah can be fully discharged or recharged in 1 hour
• 2C means discharging or charging the same battery in 30 minutes
• 0.5C means it takes 2 hours

Why is the C-value important?

• Faster energy delivery – Essential for peak load and emergency power supply
• Efficient charging – Shorter charging times optimize battery usage
• Flexible energy management – Important for peak shaving and energy trading

At ZMission, supplier of AlphaESS, we offer high-quality battery solutions with optimized C-values for efficient energy storage and release.

SOH (State of Health): The health status of your battery

State of Health (SOH) shows the overall condition and remaining performance of a battery relative to its original capacity. This percentage shows how efficiently the battery still functions and is an important indicator of longevity and reliability.

How does SOH work?
The SOH of a battery is expressed as a percentage of its original capacity.

• 100% SOH – Battery functions like new
• 80% SOH – Often the point at which performance loss becomes noticeable
• 50% SOH – The battery has lost significant capacity and is less efficient

Why is SOH important
Provides insight into battery degradation and maintenance needs
Helps with energy management by maximizing efficient use
Determines economic life and replacement times

At ZMission, provider of AlphaESS, we offer smart battery solutions with advanced monitoring from SOH to ensure energy storage remains efficient and reliable.

EOL (End of Life): The end of battery life.

End of Life (EOL) refers to the point at which a battery no longer provides sufficient capacity for its original application. Although the battery can still store energy, its efficiency has decreased to the point where replacement or reuse becomes necessary.

When does a battery reach EOL?
Batteries are usually considered end-of-life when their capacity drops below a certain percentage, often around 70 to 80 percent of their original storage capacity. This means:

• The battery can provide less energy than originally designed
• Charge and discharge times become less efficient
• Decrease in reliability and performance

What happens after EOL?
A battery that has reached the end of its life can often still be used in a secondary application, such as energy storage with lower power requirements. Recycling also plays an important role in recovering valuable materials and minimizing environmental impact.

At ZMission, supplier of AlphaESS, we offer advanced battery solutions and advise on lifecycle management, reuse and sustainable replacement options.

DOD (Depth of Discharge): How much capacity has been used

Depth of Discharge (DOD) indicates the percentage of battery capacity that has been consumed. The deeper a battery is discharged, the greater the impact on its life.

How does DOD work?
DOD is expressed as a percentage of total battery capacity.

• A DOD of 50% means the battery is discharged to half its maximum capacity
• A DOD of 80% means that 80% of the energy has been consumed, with 20% remaining power
• A DOD of 100% means full discharge, which typically shortens battery life

Balance between DOD and lifespan

• A lower DOD extends battery life because less deep discharges cause less wear.
• A higher DOD maximizes usable energy but accelerates battery cell degradation.

Optimizing DOD is critical to an efficient energy storage strategy. At ZMission, supplier of AlphaESS, battery solutions are tuned for optimal DOD balance to maximize performance and lifetime.

RTE (Round Trip Efficiency): Energy Storage Efficiency.

Round Trip Efficiency (RTE) is a measure of the efficiency of a battery energy storage system. It indicates how much of the charged energy is usable again after discharge.

How does RTE work?
During the charging and discharging of a battery, some of the energy is lost through heat generation and internal resistance. The RTE is expressed as a percentage:

• An RTE of 90% means that 90% of the input energy is available again after discharge
• An RTE of 70% means that 30% of the energy is lost during the process

Why is RTE important?

• A higher RTE lowers energy loss, saving costs
• Efficient batteries contribute to better energy storage and management
• Optimal RTE helps in sustainable and cost-effective deployment of battery systems

At ZMission, supplier of AlphaESS, battery solutions are developed with high RTE, which conserves more energy and maximizes the efficiency of energy storage.

AC/DC: Alternating current and Direct current

Alternating Current (AC) and Direct Current (DC) are the two forms of electric current that a facility can process or convert. Both types play a crucial role in energy storage, grid management and electricity distribution.

What is AC (Alternating Current)?
Alternating current constantly changes direction and is used in the power grid and most household appliances. This type of current is ideal for long-distance transmission because it can be easily increased or decreased using transformers.

What is DC (direct current)?
Direct current has a constant current direction and is used in batteries, solar panels and electronic devices. DC storage is more efficient for batteries and battery technologies because there is less energy loss.

AC/DC Conversion and Applications
In order for appliances and power systems to function properly, inverters are needed to convert AC to DC or vice versa. This is done in applications such as:

• Solar panels that generate direct current and convert it to alternating current through an inverter for use in households
• Battery storage where DC energy is stored and converted to AC for grid use when needed
• Electric vehicles that use DC charging but sometimes offer AC charging options for flexibility

At ZMission, supplier of AlphaESS, we offer battery solutions with efficient AC/DC conversion, optimized for maximum energy storage and grid integration.

What is Peak Clipping?

Peak Clipping is a method within energy management where short, extreme peaks in power consumption are smoothed using a battery system. This helps companies and energy-intensive users to reduce the maximum load (peak demand) and thus avoid high costs.

How does it work?

• During peak loads, the battery provides additional energy to reduce the load on the grid.
• This reduces the total power taken from the grid and distributes it more evenly.
• This avoids high costs charged by energy companies for peak consumption (demand charges).

Benefits of Peak Clipping:

• Lower energy costs – Reduce peak load and save on demand charges.
• More efficient energy use – More stable load prevents overloading the grid.
• Better use of renewable energy – Batteries can store surplus solar energy and use it during peak times.

Peak Clipping is often used in conjunction with Peak Shaving and energy storage systems such as AlphaESS batteries from ZMission Energy Integrators.

What is Peak Shaving?

Peak Shaving is an energy management strategy that reduces peak consumption by temporarily using energy from batteries or alternative energy sources. This helps companies and large consumers avoid high costs due to peak loads and regulate their energy consumption more efficiently.

How does it work?

• During periods of high power demand, the system automatically switches to battery storage or an alternative power source.
• This flattens the peak load on the power grid and avoids high demand charges (costs for peak consumption).
• Once demand drops again, the battery can recharge with cheap power or solar energy.

Benefits of Peak Shaving:

• Direct cost savings – Less peak consumption means lower energy costs.
  Improved energy efficiency – Prevents unnecessary load on the grid.
• Make better use of renewable energy – Store excess solar energy and use it during peak hours.
• Reduce grid congestion – Less pressure on the grid and more stable power supply.

Peak Shaving is often used in conjunction with battery systems such as AlphaESS from ZMission Energy Integrators to create smart and cost-effective energy solutions.

What is the difference between Peak Shaving and Peak Clipping?

Peak Shaving focuses on reducing structural peak loads, often over a longer period of time (e.g., an hour). This reduces overall energy costs by using batteries or alternative energy sources during peak hours.

Peak Clipping focuses on smoothing short, unexpected power spikes that last only a few seconds to minutes. This prevents equipment damage and extra costs due to extremely high spikes.

Both techniques are often combined in smart energy management systems with battery storage, such as AlphaESS from ZMission Energy Integrators, to both reduce costs and stabilize power supplies.