What Are the Effects of a Weak Car Battery?
3 Answers
If a car battery remains in a weak state for an extended period, the most immediate damage is excessive carbon buildup in the engine, leading to a significant drop in power. Here is some relevant information about car batteries: 1. Working Principle: A car battery uses lead plates filled with sponge-like lead as the negative electrode and lead plates filled with lead dioxide as the positive electrode, with a 22–28% dilute sulfuric acid solution as the electrolyte. During charging, electrical energy is converted into chemical energy, and during discharging, chemical energy is converted back into electrical energy. When discharging, metallic lead serves as the negative electrode, undergoing oxidation to form lead sulfate, while lead dioxide acts as the positive electrode, undergoing reduction to also form lead sulfate. When charging with direct current, lead and lead dioxide are regenerated at the respective electrodes. After disconnecting the power source, the battery returns to its pre-discharge state, forming a chemical cell. A lead-acid battery is rechargeable and reusable, known as a secondary battery, with a voltage of 2V. Typically, three lead-acid batteries are connected in series to achieve 6V. Cars use six lead-acid batteries connected in series to form a 12V battery pack. Regular lead-acid batteries require periodic replenishment of sulfuric acid to maintain the electrolyte at 22–28% dilute sulfuric acid. 2. Classification: Conventional batteries, dry-charged batteries, and maintenance-free batteries.
Having driven a taxi for over twenty years, the most frustrating issue with a weak battery is the difficulty in starting the car. On cold winter mornings when the temperature is low, turning the key results in the starter making a weak clicking sound, and the dashboard lights become unusually dim. If you force multiple ignition attempts in this state, the starter gears can easily wear out. Even worse, the vehicle's anti-theft system might mistakenly activate, directly locking the steering wheel. There was one time when the battery was severely aged, and the power-assisted steering wheel couldn't even turn, nearly causing an accident at an intersection. Long-term battery undercharge is even more damaging—the internal lead plates can sulfate, causing the battery's storage capacity to deteriorate rapidly, going from lasting three years to being unusable in less than three months. Now, I use a voltmeter to check the battery voltage every month, and if it drops below 12 volts, I replace it immediately.
My compact car had battery issues this year. One evening after work, the remote key fob didn't respond, and I had to use the mechanical key to open the door. Inside, the infotainment screen was completely black - navigation unresponsive and the stereo making static noises. When attempting to start, the dome light flickered before dying completely, leaving even the reversing camera inoperable. While driving, the AC suddenly stopped blowing air, and power windows became sluggish. The mechanic explained this was a chain reaction caused by battery voltage dropping below 11 volts - the ECU automatically cuts non-essential power. Low voltage also risks blowing fuses, which is how my cigarette lighter USB charger got damaged. Now I've developed the habit of always turning off headlights and AC before shutting down the engine.
