Lead and lithium batteries are both energy-storage devices that play a significant role in our lives. At one time, it seemed lithium might seize lead’s market, but this has not happened. The reason for this becomes clear when comparing lead-acid and lithium-ion batteries. In a few words, they are complementary technologies and each has their part to play.
Comparing Lead-Acid and Lithium-Ion Battery Technologies
Lead-Acid Battery Technology
A lead battery contains a number of cells, each delivering 2 nominal volts. Every one of these cells comprises a lead anode, and a separate lead-dioxide cathode. A sulfuric-acid electrolyte solution surrounds this arrangement. Electric current flows from the battery when a user creates an external circuit between the two terminals.
The difference becomes evident when comparing the chemistry of lead-acid with lithium-ion batteries. The elegantly simple design converts the lead, and lead-dioxide to lead-sulfate. Recharging returns the battery to near its original state.
Lithium-Ion Battery Technology
A lithium-ion battery comprises one or more cells. A cell in turn consists of an anode, typically graphite, and a lithium-metal cathode. An electrolyte of dissolved lithium salts completes the physical structure.
Electro-chemistry springs into action when a user connects the terminals via an external circuit. Lithium-ions travel through the electrolyte from anode to cathode energizing an external current flow. Recharging the battery returns it to near its original state.
Energy Density and Specific Energy
- Battery energy density refers to the amount of energy it can store.
- Whereas specific energy expresses this factor in terms of weight.
- While volumetric energy recalculates this in terms of battery size.
Lithium-ion batteries score hands down against lead-acid in terms of these three factors. This is why lithium batteries have cornered the market for portable, lightweight applications according to Giovanni Mori Engineering. But it’s not done and dusted for lead batteries by far. Read our next post to know the whole truth.
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Lithium-ion Battery Performance – Status Quo
