No it’s a mode where you can tell the charger to monitor the external discharge , ie making the battery discharge into an array of say light bulbs , or resistors so the unused fully charged battery discharges through them , and the charger monitors the packs cell voltage and then stops the battery from going below storage charge , so putting back to storage charge instead of leaving the battery at full charge , the battery can be discharged a lot faster as the built in discharger has limited discharge capacity .