Lead-Acid Battery Principles and Classification

Lead-acid batteries are composed of lead and its oxide for the electrodes, with sulfuric acid solution as the electrolyte. In discharge mode, the positive electrode primarily consists of lead dioxide, while the negative electrode is primarily composed of lead. In charging mode, lead-acid batteries are categorized into vented batteries and maintenance-free lead-acid batteries.

A battery typically consists of tubular positive plates, negative plates, electrolyte, separators, battery container, battery cover, terminals, and filler caps. Vented batteries have electrodes made of lead and lead oxide, with electrolyte being a water solution of sulfuric acid.

Working Principle of Lead-Acid Batteries

The positive electrode active material in lead-acid batteries is lead dioxide, while the negative electrode active material is sponge lead. The electrolyte is a diluted sulfuric acid solution. The discharge chemical reaction involves lead dioxide, sponge lead, and the electrolyte reacting to form lead sulfate and water:

Pb (negative) + PbO2 (positive) + 2H2SO4 → 2PbSO4 + 2H2O (discharge reaction)

The charging chemical reaction converts lead sulfate and water back into lead dioxide, sponge lead, and dilute sulfuric acid:

2PbSO4 + 2H2O → Pb (negative) + PbO2 (positive) + 2H2SO4 (charging reaction)

The nominal voltage of a single lead-acid battery cell is 2.0V. These cells are commonly connected in series to create 6V and 12V batteries for automotive and motorcycle starting and lighting. Individual cells are also connected in series to form 48V, 96V, 110V, or 220V batteries for various applications. Low-resistance, stable ion-conductive materials like rubber, PVC, PE, or AGM separators are used between positive and negative plates inside the battery.

 

Lead-Acid Battery Classification

1.According to relevant Chinese standards, the main battery series include:

(1)Starting batteries: Primarily used for starting and lighting in vehicles, tractors, diesel-powered ships, etc.

(2)Stationary batteries: Used for communication, power plants, computer systems as backup power sources for protection and automatic control.

(3)Traction batteries: Utilized as power sources for various battery-operated vehicles, forklifts, and loaders.

(4)Railway batteries: Employed for starting and lighting in internal combustion locomotives, electric locomotives, and passenger cars.

(5)Motorcycle batteries: Mainly used for starting and lighting in motorcycles of various specifications.

(6)Coal mine batteries: Mainly used for power supply in electric locomotives for mining.

(7)Energy storage batteries: Primarily used for storing energy from wind and hydroelectric power generation.

2.Classification based on electrode plate structure: Formed plates, paste-coated plates, and tubular batteries.

3.Classification based on battery cover and structure: Open-type, vented, acid-proof explosion-proof, and sealed valve-regulated batteries.

4.Classification based on maintenance mode: Regular maintenance, low-maintenance, and maintenance-free batteries.