All About Voltage SagUpdated a month ago

Does it seem like the battery indicator drops really quickly while pedaling along? We call this voltage sag! Experiencing voltage sag on your ebike can be concerning, but rest assured, it's a common and generally harmless occurrence. Let's delve into what voltage sag is, why it happens, and how to manage it effectively.

What Is Voltage Sag?

Voltage sag refers to the temporary drop in your ebike's battery voltage during periods of high power demand, such as when accelerating, climbing hills, or carrying a heavy load. This happens because the battery's internal resistance causes a voltage drop when a significant current is drawn. You may experience the battery indicator on your display showing less capacity than what actually exists in the battery! 

Why Does Voltage Sag Occur?

Several factors contribute to voltage sag:

• High Power Demand: Activities like rapid acceleration or steep climbs require more power, leading to a temporary voltage drop.

• Battery Characteristics: All batteries have internal resistance, which causes the voltage to drop when under load. As batteries age, their internal resistance can increase, potentially leading to more noticeable voltage sag.

Is Voltage Sag a Problem?

In most cases, voltage sag is normal and not a cause for concern. Once the high power demand decreases, the voltage typically returns to its normal level. That might mean showing up at the grocery store with 3/5 bars on the battery indicator, and leaving the grocery store with 4/5 or 5/5 bars! Crazy, right? However, if you notice significant performance issues or excessive voltage sag, it might indicate an aging battery or other underlying issues.

Managing Voltage Sag

To minimize the effects of voltage sag:

• Monitor Your Riding Habits: Avoid sudden, intense power demands when your battery is low. Gradual acceleration and maintaining a steady speed can help reduce voltage sag.

• Maintain Your Battery: Regularly charge your battery and avoid letting it fully deplete. Proper maintenance can help reduce internal resistance and prolong battery life.

• Be Mindful of Battery Age: As batteries age, voltage sag may become more pronounced. If you experience significant voltage drops, it might be time to consider replacing the battery.