Is the red terminal of a car battery positive or negative?
2 Answers
The red terminal of a car battery is positive, while the negative terminal is black. It's crucial not to reverse the connections when wiring. Reversed connections can damage all electronic devices in the vehicle. There are + and - signs marked near the battery terminals. Here's more relevant information: 1. About car batteries: The battery is an important component in a vehicle. When the engine isn't running, the battery powers all electronic devices in the car and is also responsible for starting the engine. After the engine starts, the alternator takes over to power the electronic devices and simultaneously charges the battery. 2. Battery performance: During engine startup, the starter motor requires operation, which demands the battery to release a significant current. This tests the battery's performance. If the battery performs poorly, the starter motor's rotation speed will be too low, preventing successful engine startup. The battery is a wearable part that requires regular replacement, as its performance degrades with increasing charge-discharge cycles.
I remember when I first started driving a taxi, I paid special attention to the battery connections—red is absolutely the positive terminal, almost a golden rule in the automotive world. Getting it wrong can cause serious trouble. For instance, my friend once accidentally reversed the red and black cables while repairing his car, resulting in sparks flying everywhere, blowing all the fuses, and requiring a tow for repairs, costing him hundreds for nothing. Nowadays, battery designs are standardized—red cables are thicker and come with protective covers, making it obvious they connect to the positive terminal. Also, if the battery is old and the color has faded, you can check the "+" symbol on the label or use a simple voltage tester. It’s recommended to regularly clean the battery terminals and apply a bit of petroleum jelly to prevent oxidation, which can extend the battery’s lifespan by two or three years, saving a lot of replacement hassle. During maintenance, remember to disconnect the negative terminal first, then the positive, and reverse the order when reconnecting to avoid accidental short circuits. In short, developing good habits saves time and effort—road safety relies on these small details.
