80V Cub Cadet LH3 EB Leaf Blower Replacement Battery 2500mAh

My Cub Cadet 80V blower runs full power for a few seconds then drops to almost nothing — is the battery dying or is something else wrong?

That drop pattern is thermal throttling, not a dead cell — the BMS is cutting output to protect the pack when it detects a voltage sag under the blower's high-draw motor load. It happens most often when the battery is partially charged or was stored in a hot shed, because both conditions push internal resistance up and trigger the cutoff earlier. Pull the battery off, let it cool to room temperature for 20 minutes, then charge it fully before running the blower again. If the sag still kicks in immediately on a full, cool charge, check the terminal contacts on both the battery and the tool for corrosion or debris — a dirty connection creates the same sag signature.

Replaced the battery on my Cub Cadet LM3 mower and now the charger just blinks and never goes solid — battery won't charge at all.

A blinking charge light that never goes solid usually means the pack voltage has dropped below the charger's acceptance threshold — 80V Li-ion chargers on this platform typically refuse to initiate a charge cycle if the pack reads below roughly 60V at the terminals. This happens when a replacement battery has been sitting in a warehouse for an extended period and self-discharged too deeply. Measure the pack voltage directly at the terminals with a multimeter — if you're reading below 60V, the charger won't handshake with the battery. Some chargers on this platform have a recovery or "boost" mode; check your charger model's manual for that sequence, or try a brief connection-disconnection cycle to prompt the charger to attempt a soft start.

My 80V Cub Cadet battery fits and clicks in fine but the blower won't turn on at all — no sound, no light, nothing.

A completely dead response with a battery that seats correctly usually points to the battery's protection circuit tripping into lockout mode, not a tool fault. This can happen after a deep discharge, an over-temperature event, or if the pack was stored fully discharged for more than a few months. First, press and hold the battery's charge indicator button for five seconds to check if any LEDs respond — zero LEDs means the pack is in deep protection lockout. Seat the battery into the charger for at least 30 minutes regardless of whether the charger shows a normal charge light, then retest in the tool.