winter-brodd-2004-what-are-batteries-fuel-cells-and-supercapacitors

It identifies safety-related situations that can lead to thermal runaway.

LiCoO2.

The kinetics of the electrochemical redox reactions at the electrode/electrolyte interfaces.

Approximately 30%.

To examine components of spent cells and understand degradation phenomena.

A separator is a physical barrier between the positive and negative electrodes to prevent electrical shorting.

4.0 V.

Approximately 4.6 V.

Primary batteries have non-reversible discharge reactions.

A battery that is discharged once and then discarded.

It manifests as a departure from the equilibrium or thermodynamic voltage.

Batteries provide high power while fuel cells deliver high energy.

Reactions with larger exchange current densities are more reversible and have lower polarization for a given current flow.

Greater than 50% of its theoretical value.

To describe the rate of charge-transfer-controlled battery reactions.

Primary and secondary current distribution.

Anode, cathode, and electrolyte.

Direct measurement of the instantaneous current-voltage characteristics on discharge curves.

Ohm’s law.

Fuel cells are open systems where energy storage and conversion occur in separate compartments, while batteries store and convert energy in the same compartment.

Cu is displaced by Li, forming stable products Li2S and Cu.

The redeposition is rough, mossy, and dendritic, which may cause safety problems.

Hybrid systems such as metal/air batteries.

Activation polarization, ohmic polarization, and concentration polarization.

An electrolyte provides pure ionic conductivity between the positive and negative electrodes of a cell.

About 25% of its theoretical value.

A fuel cell is an electrochemical conversion device that has a continuous supply of fuel and an oxidant.

From the size of an aspirin tablet (a few tens of mAh) to a building (40 MWh).

Open-circuit voltage is the voltage across the terminals of a cell or battery when no external current flows.

Heat is released inside the battery at the reaction site during charge or discharge.

It results in polymerization or decomposition of the solvent system.

Active masses are delivered from outside the cell, such as oxygen from the air or fuels like hydrogen and hydrocarbons.

Redox reactions at the anode and cathode.

The cathode is the positive electrode associated with reductive chemical reactions that gain electrons from the external circuit.

Batteries for notebook computers.

They all consist of two electrodes in contact with an electrolyte solution.

Operate over a wide temperature range, can deliver high current pulses, and do not require pumps or filters.

Low energy content compared to gasoline, expensive compared to coal and gasoline, and no single general-purpose system.

It increases the effective active surface area, lowering polarization.

It arises from limited mass transport capabilities, such as limited diffusion of active species to and from the electrode surface.

It provides uniform current distribution, enhancing efficiency.

It provides ionic conduction and physically separates the anode from the cathode.

1.23 V, which may expand to approximately 2 V due to kinetic effects.

It increases the surface area and shortens diffusion path lengths to the reaction site.

Primary batteries, secondary rechargeable batteries, and specialty batteries.

A rechargeable battery that can be discharged and restored to its original condition by reversing the current flow.

Modeling helps in developing new battery technology and improving the performance of existing systems.

It is directly related to the reaction rate constant, the activities of reactants and products, and the potential drop across the double layer.

Fuel cells have higher costs, inferior power and energy performance, and insufficient durability and lifetime.

10^-2 to 10^-4 seconds.

Inert parts, internal resistances, and limited utilization of active masses.

It arises from the resistance of the electrolyte, conductive diluent, and materials of construction of electrodes and current collectors.

They offer better energy efficiency and higher energy content compared to batteries.

It can lead to thermal runaway and other catastrophic situations.

They exhibit a semicircular behavior with frequency, characteristic of relaxation processes.

Conductivity of the electrode matrix, electrolyte conductivity, exchange current, diffusion characteristics, and total current flow.

Active surface area (S) and penetration depth (L_P) of the reaction process.

As power sources for heart pacemakers and military applications.

The direct relationship between the amount of reaction and the current flow.

It relates the cell voltage to the concentrations of reactants and products.

Capacitance of farads.

They heat on charge and cool on discharge.

They store energy through the orientation of electrolyte ions at the electrolyte/electrolyte interface, forming electrical double layers (EDLs).

Charge-discharge and impedance techniques.

The anode is the negative electrode associated with oxidative chemical reactions that release electrons into the external circuit.

Batteries have found the most application markets and have an established market position.

1.5 V.

The anode is the more negative electrode where oxidation occurs, while the cathode is the more positive electrode where reduction occurs.

They aim to compete with or replace batteries in several application areas.

Aqueous KOH.

Automobiles, cellular phones, notebook computers, and other portable electronic devices.

In line with the gross national product.

Electron and ion transport are separated, which is crucial for the energy-providing processes at the electrode/electrolyte interface.

It is designed to be more sustainable and environmentally friendly compared to fossil fuel combustion.

A cell or group of cells intended to be used until exhausted and then discarded.

Cell geometry and the placement of current collectors.

Greater than 70%.

A negative free energy indicates a spontaneous process with a positive electromotive force (emf).

10^-2 to 10^-3 S/cm.

Specific energy (Wh/kg) and energy density (Wh/L).

A cell that can be restored to its original charged condition after being discharged.

They extend the available surface area and lower the current density for more efficient operation.

Gibbs free energy represents the net useful energy available from a given reaction.

Liquid solvent-based electrolytes, which can be aqueous, nonaqueous, or solid.

It is forecast to have a severe future impact on world economics and ecology.

Batteries have intermediate power and energy characteristics compared to fuel cells and supercapacitors.

The Faraday constant is the amount of charge that transfers when one equivalent weight of active mass reacts.

It provides significant information about battery operation characteristics.

$48,200 million.

It compares the power and energy capabilities of different energy storage systems.

Thermal runaway occurs when the battery electrode’s reaction with the electrolyte becomes self-sustaining, leading to safety incidents.

It acts as a good reducing agent (electron donor) such as lithium, zinc, or lead.

The battery will short, releasing its full energy as heat.

Organic electrolytes show lower conductivities due to ion pair formation.

The behavior of impedance with frequency for an idealized battery system.

The frequency of the maximum semicircle gives the relaxation time, where τ = 1/fm = RC.

Batteries, fuel cells, and electrochemical capacitors (ECs).

Batteries are closed systems that store energy, while fuel cells convert chemical energy to electrical energy continuously.