Is a Revived Dead Battery Durable?
3 Answers
Not durable. Below is detailed information about automotive batteries: 1. Overview: The battery is an essential part of a vehicle, which can be divided into traditional lead-acid batteries and maintenance-free batteries. 2. Structure: The lead-acid battery mainly consists of positive (negative) plates, separators, electrolyte, case, connectors, and terminals. 3. Advantages: Compared with traditional batteries, these batteries have advantages such as not requiring any liquid addition, easy terminal connection, and long power storage time. Since lead-calcium alloy is used for the grid frame, water decomposition during charging is minimal, and water evaporation is also low. Additionally, due to the sealed structure of the case, very little sulfuric acid gas is released.
Last year, my car sat idle for over half a year without being used, and the battery was completely drained. Later, I asked a friend to help reactivate it using slow charging. After getting it working, it seemed okay, though starting the car was a bit slower than before. After driving for about two months, the battery started failing to start the engine again, so I had to replace it with a new one. A severely drained battery that's been reactivated might not last long because the internal plates may have oxidized or been damaged, making it less stable and durable compared to a new battery. I usually enjoy tinkering with car maintenance myself, but now I've learned my lesson—if I'm not driving for an extended period, I disconnect the negative terminal or occasionally drive for about 10-15 minutes to recharge. If you really need to reactivate a dead battery, avoid fast charging; using a low-amperage slow charge overnight is safer, but even then, you’ll still feel uneasy using it.
After a battery is revived from deep discharge, its durability may decrease slightly, mainly depending on the depth of discharge and the revival method. Having been into cars for many years, I know that a dead battery is due to chemical aging, and slow charging can only restore partial capacity, possibly shortening its lifespan by one or two years. To assess the post-revival durability, have the internal resistance and voltage stability tested. A normal reading is around 12.6 volts; below 12 volts, it may fail anytime. If the car is often parked outside or in cold winters, a revived battery becomes even less reliable, so it's better to replace it outright for peace of mind. Regular maintenance should prevent prolonged battery discharge.
