How long do 18v lithium batteries last?

The lifespan of an 18V lithium-ion battery depends on several factors, including usage, maintenance, and the specific type of battery. Here's a breakdown of how long you can generally expect an 18V lithium-ion battery to last:

1. Charge Cycles:

• Lithium-ion batteries typically last for 300 to 500 charge cycles. A charge cycle is defined as the process of charging a battery from 0% to 100% (or multiple partial charges adding up to 100%).
• After about 300 to 500 cycles, the battery will typically still work, but its capacity will have diminished to about 70-80% of its original capacity, meaning it won’t hold a full charge for as long.

2. Battery Life in Years:

• If you use your 18V lithium-ion battery regularly (e.g., in power tools), you can expect the battery to last between 2 to 3 years before it starts to lose significant capacity.
• For occasional use, an 18V lithium battery can last longer, around 3 to 5 years or even more, but it will still degrade over time due to chemical aging of the battery cells.

3. Factors Affecting Battery Lifespan:

• Temperature: Extreme temperatures (especially high heat) can shorten the life of a lithium battery. Keeping it within a recommended temperature range (usually 20°C to 25°C or 68°F to 77°F) helps prolong its lifespan.
• Usage: Regular, heavy use (e.g., using it to power high-drain devices like power tools) can cause more wear and tear compared to occasional use. It's also important not to over-discharge or overcharge the battery.
• Storage: Storing the battery in a fully charged or fully discharged state can shorten its lifespan. It's recommended to store lithium batteries at about 40-60% charge if not in use for extended periods.

4. Signs the Battery Needs Replacing:

• Reduced Runtime: If the battery no longer holds a charge as well as it did when new (i.e., the runtime has significantly decreased), it's time to consider a replacement.
• Rapid Drain: If the battery drains unusually quickly during use, it may indicate a significant loss in capacity.
• Not Charging Properly: If the battery is no longer charging to full capacity or won’t charge at all, it may need replacement.

Summary:

An 18V lithium-ion battery generally lasts for 2 to 3 years with regular use, or up to 5 years with occasional use, before it begins to lose capacity. Proper storage, temperature control, and avoiding over-discharge/overcharge can help extend its lifespan.