Wireless charging is a remarkably safe technology when used correctly. However, like any electrical device, there are potential hazards that users should understand. From heat management to foreign object detection, this guide covers everything you need to know to charge your devices safely and protect both your phone and your home.
After testing dozens of wireless chargers and researching safety standards extensively, we've compiled the most important safety considerations every wireless charger owner should know. Following these guidelines will help you get the most out of your wireless charger while minimising any risks.
Understanding Heat: The Primary Safety Concern
Heat is the most significant safety consideration with wireless charging. The electromagnetic induction process that enables cable-free charging is not 100% efficient—some energy is lost as heat during the transfer. This heat affects both the charger and your device.
Why Heat Matters
Excessive heat can degrade your phone's battery over time, reducing its overall capacity and lifespan. In extreme cases, overheating can trigger automatic shutdowns, damage internal components, or (very rarely with reputable chargers) create fire hazards. Lithium-ion batteries, which power virtually all smartphones, are particularly sensitive to high temperatures.
Modern smartphones and chargers have built-in thermal management systems to prevent dangerous temperatures. Your phone may slow or pause charging automatically if it gets too warm—this is a safety feature working as intended, not a malfunction.
If your phone or charger becomes uncomfortably hot to touch (not just warm), remove the phone immediately and allow both devices to cool down. Persistent overheating may indicate a faulty charger that should be replaced.
Tips for Managing Heat
- Remove thick cases: Heavy-duty or insulated cases trap heat. Consider using a slim case or removing your case during charging.
- Avoid direct sunlight: Don't place your charging setup near windows or in direct sunlight, especially during Australian summers.
- Ensure ventilation: Don't place chargers on soft surfaces like beds or couches that block airflow.
- Don't stack devices: Never place objects on top of your phone while it's charging.
- Choose quality chargers: Reputable brands invest in thermal management features that reduce heat generation.
Foreign Object Detection (FOD)
Foreign Object Detection is a crucial safety feature built into quality wireless chargers. FOD systems detect when metal objects—like coins, keys, or credit cards—are placed between the charger and phone, and automatically stop charging to prevent these objects from overheating.
Why FOD Matters
Metal objects on a wireless charger can absorb electromagnetic energy and heat up rapidly, potentially causing burns or starting fires. This is particularly concerning with items you might not immediately notice, like coins that slipped from your pocket or paper clips on a cluttered desk.
Always verify your wireless charger has FOD (Foreign Object Detection) certification. Look for Qi or Qi2 certification marks, which require FOD functionality. Avoid unbranded chargers that may lack this essential safety feature.
Best Practices for FOD
- Keep your charging area clear of metal objects
- Check under your phone before placing it on the charger
- If charging stops unexpectedly, check for foreign objects before assuming the charger is broken
- Remove credit cards, ID badges, and hotel keys from phone cases before charging
Electrical Safety Considerations
While wireless chargers eliminate the physical cable connection to your phone, they still require a wired connection to power. Electrical safety remains important.
Power Adapter Safety
Many wireless chargers come with only a USB cable, requiring you to supply your own power adapter. Using the wrong adapter can affect both safety and performance:
- Use appropriate wattage: Match your adapter to your charger's requirements. An underpowered adapter won't charge efficiently; an overpowered adapter should be fine (the charger regulates intake) but offers no benefit.
- Avoid cheap knockoffs: Non-certified power adapters may lack proper safety features and can pose electrical hazards.
- Check for damage: Regularly inspect cables and adapters for fraying, exposed wires, or damaged plugs.
- Use Australian-approved products: Look for the Regulatory Compliance Mark (RCM) on electrical products sold in Australia.
Placement and Environment
Where you place your wireless charger matters for electrical safety:
- Keep away from water: Don't use wireless chargers in bathrooms or near sinks, even if your phone is water-resistant.
- Stable surfaces only: Place chargers on stable, flat surfaces where they won't fall or be knocked over.
- Avoid flammable materials: Don't place chargers on or near papers, fabrics, or other flammable materials.
- Temperature extremes: Avoid extremely hot or cold environments, which can affect both safety and charging efficiency.
In Australia, electrical products should comply with AS/NZS standards and bear the RCM (Regulatory Compliance Mark). Products purchased from reputable Australian retailers typically meet these requirements, but be cautious with direct imports from overseas marketplaces.
Battery Health and Long-Term Safety
While not an immediate safety concern, maintaining battery health contributes to long-term device safety. Degraded batteries are more prone to issues like swelling or reduced thermal stability.
Overnight Charging
Many people worry about leaving their phone on a wireless charger overnight. Modern smartphones handle this safely through several mechanisms:
- Trickle charging: Once the battery reaches 100%, the charger reduces power to minimal levels.
- Optimised charging: iPhones and many Android phones learn your schedule and delay charging to 100% until you need the phone.
- Temperature monitoring: Devices pause charging if temperatures exceed safe thresholds.
That said, if you want to maximise battery longevity, consider setting a charging limit (available on many phones) to 80% for regular daily charging, only charging to 100% when you need maximum runtime.
Recognising Unsafe Chargers
Not all wireless chargers are created equal. Here's how to identify potentially unsafe products:
Red Flags to Watch For
- No brand name or unrecognisable brand with no online presence
- Missing Qi or Qi2 certification marks
- Unusually cheap pricing (well below similar certified products)
- No safety certifications or compliance marks
- Poor build quality, loose components, or visible defects
- Missing or illegible documentation
Where to Buy Safely
Purchase wireless chargers from established retailers like JB Hi-Fi, Officeworks, or directly from brand websites. When buying from Amazon or other marketplaces, stick to products sold by reputable brands with strong review histories and proper certifications listed.
If you notice any unusual smells (like burning plastic), sounds (buzzing or clicking), or visual issues (flickering LEDs, discoloration) during charging, disconnect the charger immediately and discontinue use. These are signs of potential electrical faults.
Summary: Your Safety Checklist
Wireless charging is a safe, convenient technology when you follow basic precautions. Here's a quick checklist to reference:
- ✓ Buy certified chargers from reputable brands and retailers
- ✓ Use appropriate power adapters with proper certifications
- ✓ Keep charging areas clear of metal objects and clutter
- ✓ Place chargers on stable, ventilated surfaces away from water
- ✓ Remove thick cases that trap heat during charging
- ✓ Monitor for excessive heat and discontinue use if concerned
- ✓ Regularly inspect cables and adapters for damage
By following these guidelines, you can enjoy the convenience of wireless charging with complete peace of mind. If you have any concerns about a specific charger, don't hesitate to reach out to the manufacturer or contact us with questions.