how do i clean my craftsman v20 battery? it's got grease and sawdust all over the contacts.

Diagnosis

The accumulation of sawdust and grease on the contacts of a CRAFTSMAN V20 battery creates a high-resistance barrier between the battery's internal cells and the tool's motor. Sawdust is an insulator; when it mixes with grease or oil, it forms a thick, conductive-blocking paste that prevents the metal terminals from making a flush connection. This often manifests as the tool cutting out during heavy loads, the charger failing to recognize the battery (flashing red lights), or the battery overheating due to voltage drops. To confirm the issue, inspect the three copper-colored contact rails on the top of the battery pack. If you see a dull film or visible clumps of debris, the electrical circuit is being compromised. You can test this by attempting to trigger the drill; if it stutters or dies despite a full charge, the contact surface is the primary culprit. Be careful not to confuse surface debris with "pitting" or carbon scoring, which are permanent burns on the metal caused by electrical arcing.

How to Fix It

Follow these precise steps to restore electrical conductivity without damaging the sensitive electronics inside the V20 pack.

1. Isolate the Battery: Remove the battery from the drill and place it on a non-conductive surface, such as a wooden workbench or a rubber mat. Ensure no metal screws or drill bits are within 6 inches of the terminals to prevent accidental short-circuiting.
2. Dry Debris Removal: Use a can of compressed air or a soft-bristled nylon brush (like a clean toothbrush) to blast away loose sawdust from the crevices around the contact rails. Do not use a metal wire brush, as this will scratch the plating and lead to faster corrosion.
3. Degreasing the Contacts: Dampen a cotton swab (Q-tip) with 90% or higher Isopropyl Alcohol. Do not pour liquid directly onto the battery. Gently scrub the three copper contact rails, focusing on the edges where grease tends to build up. The alcohol breaks down the oils and evaporates quickly, preventing moisture from entering the battery casing.
4. Mechanical Cleaning: If the grease is particularly stubborn or "caked," use a lint-free microfiber cloth dampened with alcohol to wipe the terminals in a single direction. Avoid circular scrubbing, which can push debris further into the plastic housing.
5. Final Dry: Use a clean, dry section of the microfiber cloth to buff the contacts until they appear shiny. Allow the battery to air-dry for 60 seconds before sliding it back into the V20 drill or the charger.

If That Didn't Work

• Use an Electronic Contact Cleaner: If Isopropyl alcohol isn't cutting through the industrial grease, use a specialized "Quick Dry Electronic Cleaner" spray. Spray the cleaner onto a cloth first, then wipe. These solvents are designed to remove non-conductive contaminants without leaving a residue that could attract more dust.
• Address Oxidation: If the contacts look dull or grey (oxidation) rather than just dirty, use a precision fiberglass scratch brush or a very fine polishing cloth. Gently rub the copper rails to remove the oxide layer until the bright metal is exposed.
• Inspect the Tool Terminals: The problem may not be the battery, but the corresponding pins inside the drill's battery port. Use a flashlight to check for sawdust clumps inside the tool. Use compressed air to blow out the port; if the pins are bent or coated in grease, clean them using the same alcohol-soaked swab method used for the battery.
• Check for Case Compromise: If grease has leaked into the seams of the battery housing, the internal circuitry may be contaminated. If cleaning the exterior doesn't restore power, the battery may have suffered internal failure due to contamination and will need to be replaced under warranty.

Heads Up

• Avoid Water at All Costs: Never use water, soap, or household cleaners. Water can seep into the vents of the V20 casing, causing a short circuit that can permanently kill the battery's protection circuit module (PCM).
• No Metal Tools: Never use a screwdriver, nail, or steel wool to scrape the contacts. Scratching the copper plating exposes the base metal to oxygen, which accelerates corrosion and increases electrical resistance.
• Storage Habits: To prevent future buildup, store your V20 batteries in a dedicated tool box or plastic bin rather than loose on a workshop bench where sawdust settles on them.
• Thermal Warning: If the battery feels hot to the touch after cleaning and inserting, remove it immediately. This indicates a short or a poor connection that is causing resistive heating.