Energy Storage Technologies Overview

A measure of how easily an electrode gains electrons (reduction). It determines the spontaneity of a redox reaction, and is measured in volts.

Batteries have three key parts: a negative anode, a positive cathode, and an electrolyte separating them.

During discharge, electrons move from the negative anode to the positive cathode through a connected wire.

More positive SRP values indicate more spontaneous reduction reactions.

Ions move between the electrodes through the electrolyte during battery discharge.

The SRP value of the substance being reduced (at the cathode).

During charging, electrons flow from the cathode to the anode, and ions move to their original electrodes.

The SRP value of the substance being oxidized (at the anode).

The opposite of reduction (loss of electrons) at the anode. Its SRP is opposite in sign.

Battery efficiency is around 80-85% because of internal resistance and some heat loss.

A series battery arrangement adds voltages of individual batteries.

Batteries slowly lose their charge over time due to ongoing chemical reactions.

Batteries connected end-to-end, with the positive terminal of one connected to the negative terminal of the next.

A chemical reaction consisting of oxidation and reduction reaction (both happening at the same time).

The voltage of a battery comes from chemical reactions that produce electrons at one electrode and consume them at the other (oxidation and reduction).

Batteries connected side-by-side, with the positive terminals connected and the negative terminals connected.

The voltage of a single battery when connected in parallel circuits

The combined current output of all batteries when connected in parallel

Total charge a battery can hold (current x time)

Power loss due to internal resistance (current squared x resistance)

Energy a battery can store (voltage x capacity (Ah))

Voltage needed to charge a battery to completion.

Battery voltage decreases during discharge due to internal resistance.

Energy storage technologies can be categorized based on the way energy is stored. Common types include electrochemical (batteries, fuel cells), electromagnetic (capacitors), thermodynamic (compressed air, ice, molten salt), and mechanical (pumped hydro, flywheels).

This type of energy storage uses chemical reactions to store and release energy. Examples include batteries and hydrogen fuel cells.

During discharge, electrons move from the anode to the cathode through a conductor, while ions move through the electrolyte. This is like a chemical reaction releasing energy. During charging, the process is reversed, electrons flow from cathode to anode, ions move back, and energy is stored.

Voltage in a battery arises from chemical reactions at the electrodes. Oxidation occurs at the anode (loss of electrons), and reduction occurs at the cathode (gain of electrons). These reactions create a potential difference, resulting in voltage.

These devices convert stored chemical energy in hydrogen into electricity through a chemical process. They offer a potential solution for energy storage and clean energy production.

The Standard Reduction Potential (SRP) measures how easily a substance gains electrons (reduction) in a redox reaction. It is measured in volts and indicates the spontaneity of the reaction.

A more positive SRP value indicates a more spontaneous reduction reaction. This means the substance is more likely to gain electrons.

The SRP at the cathode is positive because reduction is occurring, meaning the substance is gaining electrons. At the anode, the SRP is negative because oxidation is occurring, meaning the substance is losing electrons.

The total voltage of a battery is the sum of the SRP at the cathode (positive) and the inverse of the SRP at the anode (also positive).

In a series arrangement, the anode of one battery connects to the cathode of the next, and so on. This adds up the individual voltages of each battery.

In a parallel arrangement, all anodes are connected together and all cathodes are connected together. This increases the current capacity but keeps the voltage the same as a single battery.

At the anode, oxidation occurs, meaning the substance loses electrons. The SRP for oxidation is the inverse of the SRP for reduction (a negative value).

The SRP measures the spontaneity of reduction, but at the anode, oxidation (loss of electrons) is occurring. So, the SRP for the anode is expressed as a negative value.

When batteries are connected in series, the total voltage is the sum of the individual battery voltages.

The amount of electrical charge a battery can store, measured in Amp-hours (Ah).

The total amount of energy a battery can store, measured in Watt-hours (Wh).

As a battery discharges, its voltage decreases due to internal resistance and power loss.

Lower temperatures reduce the rate of chemical reactions within a battery, leading to decreased charge availability.

Buildings consume a large portion of energy, especially for heating and cooling.

The process of heating or cooling a building to maintain a comfortable temperature.

The transfer of heat through direct contact between materials.

Heat transfer through the movement of fluids (liquids or gases).

A measure of how easily heat flows through a material.

The opposite of thermal conductance, indicating how well a material resists heat flow.

A measure of how much heating or cooling a building needs based on the difference between the average daily temperature and a comfort setpoint.

The potential to reduce energy consumption through upgrades and technologies in buildings.

Indicates how well a building material insulates against heat loss or gain. A higher R-rating means better insulation.

Represents how easily heat can pass through a building component, like a wall or window. A lower U-value signifies better insulation.

The greater the temperature difference between the inside and outside of a building, the more significant the heat transfer will be.

Heat transfer due to the physical movement of air in and out of a building. It's influenced by building volume, temperature difference, and ventilation rates.

Ventilation is crucial for healthy indoor environments but also a major source of energy consumption in commercial buildings.

Common methods of heating a building include furnaces and electric heaters.

Air conditioning units work by using a refrigerant to absorb heat from a warm area and release it outside, cooling the enclosed space.

Refrigerant, like ammonia, changes state from liquid to gas, absorbing heat, and then back to liquid, releasing heat, to achieve cooling.

Buildings are responsible for 40% of the US primary energy use and 70% of its electricity consumption, mainly due to heating and cooling needs.

Heat moves through a material by direct contact, like touching a hot stove. The hotter the material, the more heat it transfers.

Heat transfer through the movement of fluids (liquids or gases). Think of hot air rising and cold air sinking.

Measures how easily heat flows through a material. A high U-value means heat passes easily, like a thin window.

Measures a material's ability to resist heat flow. Think of thick insulation on a wall.

A measure of how much heating or cooling a building needs based on daily temperature differences.

While efficiency can reduce energy use, sometimes it can lead to increased energy use for certain technologies, like lighting.

Represents how easily heat can pass through a building component, like a wall or window. A lower U-value signifies better insulation. For example, a window with a U-value of 0.3 will allow less heat to pass through than a window with a U-value of 1.