Which of the following statements is true of recombinant batteries?
A. They recombine oxygen.
B. They’re able to produce a higher voltage.
C. They’re vented to release gassing.
D. They recombine sulfuric acid.
The Correct answer and Explanation is:
The correct answer is A. They recombine oxygen.
Recombinant batteries, commonly known as sealed lead-acid (SLA) or valve-regulated lead-acid (VRLA) batteries, are designed to internally recombine the gases generated during the electrochemical process rather than releasing them into the environment. This process involves the recombination of oxygen, which occurs at the positive plate.
Explanation:
In a lead-acid battery, when the battery is being charged, water in the electrolyte can break down into hydrogen and oxygen gases through a process called electrolysis. In traditional flooded lead-acid batteries, these gases are vented out, which can lead to a loss of water over time, requiring regular maintenance such as adding distilled water to the cells.
However, in recombinant batteries like VRLA, this gas management process is handled internally. Oxygen generated at the positive plate during the charging process diffuses through the separator and reacts with the hydrogen at the negative plate to form water. This water is then returned to the electrolyte, preventing significant water loss and allowing the battery to operate in a sealed manner. This process is referred to as oxygen recombination, and it eliminates the need for regular maintenance associated with adding water.
Why the Other Options Are Incorrect:
- B. They’re able to produce a higher voltage: Recombinant batteries do not inherently produce a higher voltage compared to traditional lead-acid batteries. Their voltage output is the same as a standard lead-acid battery, typically 2.1 volts per cell.
- C. They’re vented to release gassing: One of the key features of recombinant batteries is that they are sealed and do not vent gases under normal operation. Venting only occurs in rare cases of overpressure to ensure safety.
- D. They recombine sulfuric acid: While sulfuric acid is present in the electrolyte, it is not recombined. The recombination process in recombinant batteries specifically refers to the oxygen and hydrogen gases.
In summary, recombinant batteries excel in low maintenance, sealed operation, and safety by recombining oxygen internally.