Sherpa SX-LIS06B 11.1V Replacement Battery 3000mAh

My Sherpa trimmer cuts out under load but works fine on light grass — what's wrong?

This is a voltage sag issue: the cell pack drops below the protection threshold when the motor draws hard current, and the BMS trips the cutoff to prevent damage. It's common in 3S Li-ion packs when one of the three cells has drifted lower than the others, which forces the whole pack offline before the others are depleted. Check the resting voltage across the pack — a healthy 11.1V 3S battery should sit between 11.7V and 12.6V after a full charge; anything under 11.4V at rest means a weak cell is dragging the group. If the charger shows full but resting voltage is low, the pack needs replacing, not recharging.

Charged this overnight and the trimmer still feels sluggish and weak compared to the old battery — is something wrong with how it's breaking in?

Li-ion cells don't need break-in cycles the way NiMH does, so sluggishness on a new pack usually points to a seating or contact issue rather than chemistry. The SX-LIS06B battery bay contacts can oxidize or sit slightly proud, which adds resistance and reduces the voltage the motor actually sees. Pull the battery, clean the gold contacts on both the pack and the tool with a dry cloth, reseat firmly, and check whether the sluggishness changes. If it's still weak after that, measure pack voltage under load — a healthy 3000mAh 3S pack should hold above 10.5V when the blade is spinning.

Charger finished but the battery is warm — warmer than my old one ever got — is that normal or is something wrong?

A 3S Li-ion pack running warmer than expected after a charge usually means the charger is delivering current faster than the cell can absorb cleanly, or one cell is internally resistive and converting more energy to heat than the others. Mild warmth — where you can hold it — is normal at end of charge; heat you can't hold for three seconds is not. Let it cool to room temperature before use and check whether it happens again on the next cycle. If the pack is consistently hot after every charge, measure resting voltage immediately after cooling — an imbalanced pack will often read 12.0V or below when a healthy one should be near 12.6V.