September 1, 2026 — A Hercules 20V 5 Ah Lithium Ion Battery reportedly exploded on a consumer’s back porch, igniting a porch fire and damaging multiple battery chargers. The incident highlights potential fire hazards associated with lithium-ion batteries, even when not in use or on charge.
Product Details
Incident Overview
On August 12, 2026, a consumer reported that a HERCULES 20V 5 Ah Lithium Ion Battery spontaneously exploded on their back porch. The explosion initiated a porch fire, which subsequently burned two DeWalt battery chargers, one Hercules battery charger, and one Kobalt charger.
According to the report, the battery was not connected to a charger at the time of the incident, nor had it been charged for over two months. Furthermore, none of the damaged chargers were plugged in; they were all sitting idle on a tote on the porch, awaiting relocation to a garage. The UPC on the battery was rendered illegible due to the fire, but the serial number 369952147 was provided. Photos of the damaged battery, porch, and chargers were submitted with the incident report, illustrating the extent of the property damage incurred. The consumer was advised to report the incident due to the potential hazard it may pose to others.
Safety Concerns
This incident raises significant safety concerns regarding the stability and potential hazards of lithium-ion batteries, specifically the HERCULES 20V 5 Ah model, even under seemingly safe storage conditions.
- Immediate Dangers: The primary immediate danger is the risk of fire and explosion. Such an event can lead to rapid ignition of surrounding materials, causing significant property damage and posing a severe burn hazard to anyone nearby.
- Long-Term Risks: The fact that the battery exploded while idle and uncharged for an extended period suggests a potential internal defect or instability that can manifest without warning. This makes these batteries unpredictable and a potential fire risk even during passive storage.
- Who Might Be Affected: Consumers who own HERCULES 20V Lithium Ion Batteries, particularly the 5 Ah model, are at risk. This includes homeowners, hobbyists, and professionals who use Hercules power tools and store these batteries in or around their homes or workplaces.
- Property Damage Potential: As demonstrated by the porch fire and destruction of multiple chargers, the property damage potential is high. Fires initiated by exploding batteries can quickly spread to structures, causing extensive damage and potential loss of life.
What Consumers Should Do
Given the reported incident, consumers who own HERCULES 20V Lithium Ion Batteries should take precautions:
- Immediate Steps to Take:
- If you notice any swelling, overheating, strange odors, or smoke coming from your battery, immediately move it to a safe, non-combustible outdoor location away from any structures or flammable materials.
- Do not attempt to charge or use a battery that shows any signs of damage or malfunction.
- How to Check If You Own the Affected Product:
- Inspect your power tool batteries for the “HERCULES” brand name and confirm they are the 20V Lithium Ion type, especially the 5 Ah model. While a specific serial number was provided for the incident, the concern applies to the product line.
- Prevention Measures:
- Store all lithium-ion batteries in a cool, dry place, away from direct sunlight, extreme temperatures, and flammable materials.
- Never store batteries in a location where they could be exposed to moisture.
- Avoid storing batteries for extended periods in locations where a fire could easily spread to valuable property or compromise safety (e.g., bedrooms, near exits).
- Do not store batteries on charge unattended or overnight.
- Regularly inspect batteries for any signs of physical damage, swelling, or corrosion. Discontinue use immediately if any issues are observed.
- Reporting Procedures:
- If you experience a similar incident or observe a malfunction with a HERCULES 20V Lithium Ion Battery, report it immediately to the U.S. Consumer Product Safety Commission (CPSC) at www.cpsc.gov.
- Also, contact Harbor Freight Tools directly to report the incident.
Manufacturer’s Response
Harbor Freight Tools responded on August 27, 2026, stating that they thank the customer for bringing the report to their attention. Harbor Freight takes all incident reports seriously and is investigating these concerns. They are in communication with the affected customer and are seeking the return of the unit involved for inspection. While the cause of the incident has not yet been determined, Harbor Freight stresses the importance of keeping battery packs dry and storing lithium batteries in a dry, indoor area at room temperature. Consumers with questions about products purchased at Harbor Freight Tools are encouraged to contact them at 800-444-3343.
Legal Help Available
If you or a loved one has been injured by a defective product or suffered property damage due to a product malfunction, you may be entitled to compensation. The experienced product liability attorneys at Farzan Law understand the complexities of defective product cases and can help you navigate the legal process. Farzan Law is a California based Personal Injury law firm focusing on protecting the rights of those wrongfully injured.
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Note: This information is based on incident reports provided by the U.S. Consumer Product Safety Commission. If you find information that is incorrect, please contact us immediately so we can correct the post to reflect accurate information.
Disclaimer: The information provided in this post is not intended to be legal or medical advice. This article is based on publicly available incident reports. The incidents mentioned have not necessarily been independently verified or adjudicated.