In the pursuit of more efficient and cost-effective battery solutions, the combination of copper
and zinc electrodes is becoming a pearl in the field of energy storage technology due to its unique
performance advantages and significant cost-effectiveness. How can this seemingly traditional
“golden pair” be revitalized in modern technological applications?
Core advantage: the perfect balance of performance and cost
The powerful combination of copper and zinc electrodes stems from their irreplaceable physicochemical properties:
Copper electrodes: the “highway” of electric currents
Excellent electrical conductivity: Copper is one of the most conductive metals in nature (second only to silver),
which greatly reduces the resistance loss inside the battery, significantly improves the energy conversion efficiency,
and ensures the smooth and efficient flow of current.
Excellent Stability: It shows good chemical stability in the battery working environment (especially neutral or
alkaline electrolyte), and is not easy to be corroded or have side reactions, which ensures the long-term integrity
and service life of the electrode structure.
Ideal current collector: Often used as a collector (e.g. copper foil), it provides a strong electron transport
channel for the active material and is the basis for building a highly efficient battery structure.
Zinc electrodes: the “powerhouse” of energy
High electrochemical activity: Zinc has a low redox potential and a high theoretical specific capacity (820 mAh/g),
which means that it can store and release more electricity, making it an excellent active material for negative electrodes.
Abundant resources, low cost: Zinc is a metal with abundant reserves and mature mining and smelting on the earth,
and the cost of raw materials is much lower than that of lithium and cobalt, which lays a solid foundation for the
large-scale production of cost-effective batteries.
High safety and environmentally friendly: Zinc itself is non-toxic, and zinc-based battery systems (such as zinc
manganese, zinc air, zinc ion batteries) usually use aqueous electrolytes, avoiding the risk of flammability
and explosiveness of organic electrolytes, which is safer and easier to recycle and dispose of.
Synergistic effect: 1+1>2 chemical reaction
When copper and zinc work together in a particular battery system, they produce much more than a single material:
Efficient energy transfer: The high conductivity of copper ensures that electrons generated by the zinc electrodes
during charging and discharging are exported to external circuits quickly and with low loss, maximizing energy
utilization.
Stable structural support: Copper collectors provide a strong backbone for zinc (or its composites), buffering zinc
from volume changes (e.g., dissolution/deposition) during the reaction process, inhibiting dendrite growth, and
improving cycling stability.
Low-cost and high-efficiency: Both are low-cost materials, the combination of which significantly reduces the
overall manufacturing cost of the battery, making it particularly suitable for large-scale energy storage or
consumer electronics, which are extremely price-sensitive.
Applications: from everyday life to future energy
Copper-zinc combination electrodes play a key role in a variety of battery technologies:
Primary batteries (non-rechargeable):
Zinc-manganese dry batteries: This is the most common application. The zinc cartridge serves as the
negative electrode and container, the intermediate carbon rod is the positive electrode collector (often
containing graphite and manganese dioxide), and the electrolyte is an ammonium chloride/zinc chloride
paste. Copper is usually present in the form of copper-plated steel shells or connectors to ensure efficient
current output. Their low price makes them an absolute staple for remote controls, clocks, toys and other devices.
Alkaline Zinc-Manganese Battery: A performance upgrade. Press-molded using high-purity zinc powder
(negative active substance), usually close to the steel case (negative collector). Positive manganese dioxide
mixed with graphite is compacted into the inner wall of the steel case (the steel case acts as the positive
collector and is protected from corrosion by nickel and other coatings), and the electrolyte is a strong
alkaline potassium hydroxide solution. Copper is often used for internal connectors or terminals. Its higher
capacity and longer shelf life are widely used in high power consumption devices such as digital cameras
and electric toys.
Secondary Battery (Rechargeable):
Zinc ion batteries: Emerging energy storage technology. Zinc is used as the negative electrode active
material in a reversible dissolution/deposition reaction on a copper (or carbon) collector. The positive
electrode is usually an oxide such as manganese-based, vanadium-based, or Prussian blue analog.
Aqueous electrolytes provide high safety. The high conductivity and stability of the copper collector is
essential to enhance the multiplier performance and cycle life of the battery. The technology shows great
potential for large-scale energy storage (grid peaking, grid-connected renewable energy) and backup power.
Zinc-air battery: Utilizing oxygen in the air as the positive reactant, the theoretical energy density is extremely
high. Zinc is used as the anode reactive material, and copper is usually used as the collector and support structure.
Mainly used in hearing aids, IoT nodes and other long range demand scenarios, and actively exploring the
application of electric vehicle range extender.
Nickel-zinc batteries: nickel oxide at the positive pole and zinc at the negative pole. It has high specific energy
and power density, and good low temperature performance. Copper plays an important role in the negative
electrode collector and connection. It has applications in power tools, light electric vehicles, and uninterruptible
power supplies.
Frontier Exploration:
Batteries for flexible/wearable devices: Utilizing the excellent flexibility and conductivity of copper foil/mesh,
combined with the processability of zinc-based materials, to develop thin, lightweight, bendable batteries to
power devices such as smart bracelets and electronic skin.
Low-cost energy storage system: Utilizing the significant cost advantages of the copper-zinc combination,
develop long-life, high-security, low-cost energy storage battery systems for home energy storage,
communication base station backup power and other scenarios.
Advanced Electrode Structures: Investigate the construction of 3D nanostructures (e.g., copper foam, copper
nanowire arrays) on copper collectors or the development of copper-zinc composites to further enhance
the stability and multiplicative performance of zinc electrodes.
Challenges and the future: Continuous optimization with unlimited potential
Despite their advantages, copper-zinc combinations also face challenges in their applications:
Zinc negative electrode issues: In rechargeable systems, uneven zinc deposition (dendrite growth) can lead to short
circuits; zinc deformation during cycling and hydrogenation reactions can also affect lifetime.
Electrolyte optimization: search for new electrolytes (additives, high concentration electrolytes, etc.) that are more
effective in inhibiting side reactions and improving the reversibility of zinc deposition/dissolution.
Interfacial engineering: Improvement of the interfacial stability between the copper collector and the zinc activator
to reduce the contact resistance.
Research to address these challenges is in full swing:
Surface modification: building zinc-friendly coatings (e.g. carbon layers, metal oxides, polymers) on the surface
of the copper collector to induce homogeneous nucleation of the zinc deposits.
Electrolyte innovation: Development of new additives, gel/solid electrolytes, inhibition of dendrites and side reactions.
Structural Design: Design of 3D copper collectors with large surface area and sufficient space to accommodate the volume change of zinc.
Zinc Alloying: Development of zinc-based alloy anodes (e.g. Zn-Mn, Zn-Ca) to improve their electrochemical performance.
Conclusion.
The pairing of copper and zinc electrodes is an example of “pragmatism” in materials science. They are not the most advanced,
high-energy combinations, but they are solutions that strike an excellent balance between cost, performance, safety and sustainability.
From the dry batteries we use every day to the large-scale energy storage systems that will support the smart grid of the future,
these “golden pairs” have shown strong vitality and broad application prospects.
As researchers continue to make breakthroughs in material modification, interface regulation, electrolyte innovation and
structural design, the performance shortcomings of copper-zinc battery system are being overcome one by one. Its inherent
advantages of low cost, high safety and environmental friendliness will enable it to play an increasingly important role
in the pursuit of an economically efficient, safe, reliable, green and sustainable global energy future. The copper-zinc
combination, the classic pair of electrode materials, is being given a new mission to continue to light the way to a
better energy future.