Is it necessary to fully discharge a new battery before its first charge?

[LenaDella]

It is not necessary to fully discharge a new battery before its first charge. In fact, completely draining the battery can damage it. The battery is a crucial component of an electric vehicle and is also a wear-prone part. As the number of charge-discharge cycles increases, the battery's performance will decline, so it requires regular replacement. Additional information: The timing for charging can be referenced as follows: 1. When the battery is 100% discharged, the charging time is typically around 8 to 10 hours, but should not exceed 12 hours (as it may affect battery lifespan). It is not advisable to fully discharge the battery every time it is used. Generally, it is recommended to charge the battery when about 70% of its capacity is used, with a charging time of approximately 6 to 8 hours. 2. For short-distance usage, the following recommendations apply: If daily usage is around 10%, charge once a week. For 20% daily usage, charge every three days. For 30% daily usage, charge every two days. For daily usage above 40%, charge once a day, controlling the charging time to around 6 hours.

[StBrynlee]

I've been repairing cars for over twenty years, and that statement is completely outdated. Modern car batteries are either maintenance-free lead-acid batteries or AGM batteries, which don't require any deliberate discharging at all. New batteries come pre-charged to about 80% capacity from the factory and can be installed directly in the vehicle. Forcing a complete discharge actually harms the battery—excessive discharge can lead to sulfation of the plates, significantly shortening the battery's lifespan. I've seen many car owners go through this hassle, only to have their new battery fail within three months. Under normal driving conditions, the alternator automatically recharges the battery. If the car is parked for more than two weeks, just start the engine and let it run for half an hour to recharge. Remember, car batteries are just like smartphone batteries—keeping them charged as you use them is the most scientific approach.

[ElliottFitz]

Last week, I replaced the battery in my car and specifically consulted the battery manufacturer's engineer. He said that when using a brand-new battery for the first time, there's no need to fully discharge it before charging. On the contrary, modern batteries are most afraid of deep discharge, as completely draining the battery might render it useless. The correct approach is to start the engine directly after installation, allowing the alternator to charge it. Based on my recent tests, the battery voltage stabilizes at 12.6V after being fully charged. If the voltage of a new battery you purchase is below 12.4V, it indicates prolonged storage, and you should request a replacement from the seller. For daily use, remember not to keep the audio system on for too long after turning off the engine, as it can easily drain and damage the battery.

[EstherFitz]

As a car enthusiast, I've studied battery principles. Modern lead-acid batteries don't have memory effect, so there's no need to fully discharge before recharging. For a new battery's first use, it's recommended to pre-charge it to around 12.7V using a charger. After direct installation and startup, the engine running for 30 minutes can fully charge it. Special note: deep discharge can imbalance electrolyte concentration and accelerate plate corrosion. I've measured that new batteries typically show voltage above 12.5V - values below this indicate need for supplemental charging. Daily use should avoid frequent short trips with engine start-stop; each drive should exceed 20 minutes to ensure sufficient charging.