The core difference is that a lithium battery is a primary (non-rechargeable) battery, while a lithium-ion battery is a secondary (rechargeable) battery. They are two distinct classes of products with completely different working principles, structures, and applications.

Despite their similar names, "lithium battery" and "lithium-ion battery" represent fundamentally different battery technologies. This naming similarity often leads to confusion. This article will systematically explain the differences and relationship between the two from the perspectives of working principles, chemical composition, performance characteristics, and application scenarios.

1. Core Differences Overview

For ease of understanding, here is a comparison of their key distinctions:

2. In-Depth Analysis of Working Principles & Chemical Composition

2.1 Lithium Battery: A "Consumable" Chemical Power Source

The lithium battery is one of the ultimate forms of primary chemical power sources. Its core is the use of metallic lithium as the negative electrode active material. During discharge, lithium metal atoms are oxidized into lithium ions (Li⁺), releasing electrons to generate current. These lithium ions migrate through the electrolyte to the cathode (typically made of materials like manganese dioxide or carbon monofluoride) and undergo an irreversible chemical reaction.

Key Point: The discharge process permanently consumes the metallic lithium at the anode. Once the lithium metal is depleted, the battery's life ends; it cannot be restored by applying a reverse current. It functions like a "chemical fuel rod" that cannot be refueled after burning out.

2.2 Lithium-Ion Battery: An "Energy Storage" System Based on Ion Shuttling

The lithium-ion battery is an advanced electrochemical energy storage device. Its ingenuity lies in the fact that both its cathode and anode materials act as "hosts" for lithium ions (e.g., cathode: lithium cobalt oxide, lithium iron phosphate; anode: graphite). During charge and discharge, lithium ions (Li⁺) shuttle back and forth like a "rocking chair," embedding into and extracting from the electrodes, while the structure of the electrode materials remains largely stable.

• During Charging: External electrical energy "pulls" lithium ions out of the cathode material, drives them through the electrolyte, and "pushes" them into the layered structure of the anode material for storage (while electrons flow to the anode via the external circuit).

• During Discharging: The process reverses. Lithium ions de-intercalate from the anode, return to the cathode, and electrons do work through the external circuit.

Key Point: No metallic lithium is generated or consumed in this process; only the state and position of the lithium ions change. This reversibility is the physical foundation for its ability to be repeatedly recharged.

3. Relationship: Technological Evolution & Market Application

There is a clear relationship of technological generational evolution and market complementarity between the two.

• From "Lithium" to "Lithium-Ion" was a Safety Revolution: Primary lithium batteries using metallic lithium were introduced as early as the 1970s. Although they offered high energy density, metallic lithium easily formed dendrites during repeated charging/discharging. These dendrites could pierce the separator, causing short circuits, fires, or even explosions. This made rechargeable metallic lithium batteries impossible to commercialize safely. The concept of the lithium-ion battery (first commercialized by Sony in 1991) emerged precisely to solve this fundamental safety issue—by replacing the dangerous metallic lithium anode with stable lithium-intercalation compounds, thereby ushering in the era of rechargeable lithium technology.

• Clear Demarcation in Applications, Forming a Complementary Landscape:

  • Lithium Batteries, with their ultra-long shelf life and extremely high volumetric energy density, firmly dominate niche markets requiring low power, long life, and single-use power. Examples include pacemakers, which require batteries to operate reliably for over a decade; CMOS batteries on computer motherboards needing minimal self-discharge to preserve BIOS settings; and certain special military and industrial applications.

  • Lithium-Ion Batteries dominate all modern mobile and high-power energy fields requiring repeated charging/discharging. From smartphones and laptops to electric vehicles and home energy storage walls, their high cycle life and good power performance are irreplaceable.

4. Conclusion

In summary, the fundamental difference between lithium batteries and lithium-ion batteries can be boiled down to this: the former is a "consumable," while the latter is an "energy storage vessel."

• The differences are fundamental: From chemical principle (consumption vs. shuttling) and core materials (metallic lithium vs. lithium compounds) to final product properties (single-use vs. rechargeable), they belong to different battery categories.

• The relationship is historical and complementary: Lithium-ion battery technology evolved from overcoming the safety limitations of primary lithium batteries. In today's market, they do not simply replace each other but form a long-term complementary coexistence based on their respective irreplaceable performance advantages.

Understanding this distinction is crucial for correctly selecting and using batteries, interpreting technical news, and grasping trends in the energy storage industry. In the future, with the development of new technologies like solid-state lithium-metal batteries (which attempt to reintroduce high-energy-density metallic lithium anodes while addressing safety with solid electrolytes), these two technological paths may see new intersections and breakthroughs.