Lithium-ion batteries can be EXTREMELY DANGEROUS if mishandled. They can catch fire, explode, or release toxic fumes.
DO NOT proceed unless you understand and accept these risks.
If you are uncomfortable with battery safety or unsure of any procedure, DO NOT BUILD OR USE THIS KIT.
¶ Fire and Explosion Risk
Lithium-ion batteries can experience thermal runaway, resulting in:
- Intense fire that is difficult to extinguish
- Explosion with projectile fragments
- Release of toxic, flammable gases
- Temperatures exceeding TODO °C
- Overcharging: Exceeding maximum voltage (typically TODO V per cell)
- Over-discharging: Dropping below minimum voltage (typically TODO V per cell)
- Excessive current: Charging or discharging too rapidly
- Physical damage: Puncture, crushing, or deformation
- Short circuit: Direct connection of positive and negative terminals
- High temperature: Exposure to heat sources or poor ventilation
- Manufacturing defects: Low-quality or counterfeit batteries
✓ Use ONLY batteries meeting specifications in BOM
✓ Purchase from reputable suppliers
✓ Verify battery specifications before use
✓ Check for physical damage before installation
✗ Never use:
- Damaged, swollen, or leaking batteries
- Batteries of unknown specification
- Batteries exceeding rated capacity
- Counterfeit batteries
- Batteries with damaged protection circuits
✓ Charge in fireproof container or on non-flammable surface
✓ Charge in well-ventilated area
✓ Monitor battery during initial charge cycles
✓ Never leave charging battery completely unattended for extended periods
✓ Keep fire extinguisher nearby (Class D or ABC rated)
✓ Charge at room temperature (TODO to TODO °C)
✓ Stop charging if battery becomes hot (>TODO °C)
✗ Never:
- Charge batteries faster than rated charge rate
- Charge in enclosed space without ventilation
- Charge near flammable materials
- Charge damaged batteries
- Exceed maximum charge voltage (TODO V per cell)
- Leave charging overnight without monitoring
✓ Monitor battery temperature during discharge
✓ Disconnect if battery becomes hot
✓ Respect maximum discharge current
✓ Stop using if voltage drops below minimum (TODO V per cell)
✗ Never:
- Short circuit battery terminals
- Expose to high temperatures
- Discharge below minimum voltage
- Exceed maximum discharge current
- Use damaged batteries
✓ Store at partial charge (TODO% to TODO%)
✓ Store in cool, dry location (TODO to TODO °C)
✓ Store in fireproof container
✓ Keep away from metal objects
✓ Inspect regularly for swelling or damage
✗ Never:
- Store fully charged for extended periods
- Store in hot locations (>TODO °C)
- Store with exposed terminals
- Store damaged batteries with good ones
- Do not dispose of lithium-ion batteries in regular trash
- Take to designated battery recycling facility
- Discharge to storage voltage before disposal (TODO V per cell)
- Tape over terminals to prevent short circuit
- Follow local regulations for battery disposal
- Evacuate immediately if fire spreads or you cannot control it
- Use Class D or ABC fire extinguisher
- Water can be used in large quantities (floods battery, cools fire)
- DO NOT use small amounts of water
- Expect multiple reignitions - battery may continue burning
- Allow battery to burn out in controlled area if safe to do so
- Call emergency services (fire department)
Note: Lithium battery fires are difficult to extinguish and may reignite multiple times.
- STOP using immediately
- Do not charge or discharge
- Place in fireproof container
- Move to safe, outdoor location if possible
- Monitor for signs of thermal runaway
- Dispose of properly at recycling facility
- DO NOT touch electrolyte
- Wear protective gloves and eyewear
- Place battery in sealed plastic bag
- Dispose of immediately at hazardous waste facility
- Wash any contacted skin with soap and water
- Seek medical attention if electrolyte contacts eyes or ingested
- Immediately disconnect from charger
- Move to fireproof container
- Take to safe, outdoor location
- Monitor for fire
- Allow to cool
- Do not reuse - dispose of properly
- Verify correct voltage and polarity before connecting
- Use only power supplies meeting specifications (TODO V, TODO A)
- CRITICAL: Reversed polarity can cause immediate battery damage and fire risk
⚠️ WARNING: Test circuit WITHOUT battery first
- Perform initial testing without battery connected
- Verify all voltages and functionality before battery connection
- Use multimeter to verify battery polarity before connection
- Be prepared to quickly disconnect power if problems occur
- Ensure all battery connections are secure
- Use wire gauge appropriate for current (TODO AWG minimum)
- Never allow battery terminals to touch
- Clearly label positive and negative terminals
- Inspect connectors regularly for damage
- Use ESD wrist strap when handling ICs
- Store components in ESD-safe packaging
- Touch grounded object before handling components
- Use insulated probes for measurements
- Never measure with wet hands
- Be aware of exposed high-current terminals
- Disconnect power before modifying circuit
- Ensure adequate ventilation during operation
- Charge batteries in well-ventilated area
- If battery vents gases, evacuate area immediately
- Operate within specified temperature range (TODO to TODO °C)
- Avoid direct sunlight on batteries
- Ensure adequate cooling during high-current operation
¶ Legal and Regulatory
- TODO: CE marking requirements
- TODO: Safety certifications
- TODO: Regional battery regulations
- This device may not meet all regulatory requirements for commercial use
- Intended for educational/hobbyist use only
- You are solely responsible for safe construction and operation
- Follow all local laws and regulations regarding lithium-ion batteries
- UnderBaked is not liable for damage, injury, or fire resulting from use of this kit
- Multimeter (accurate voltage measurement)
- Fire extinguisher (Class D or ABC)
- Fireproof charging container
- Safety glasses
- Well-ventilated workspace
- Smoke detector
- Battery temperature monitor
- ESD wrist strap
- Insulated tools
- Disconnect power before touching victim
- Call emergency services
- Begin CPR if qualified and necessary
- Eyes: Flush immediately with water for 15 minutes, seek immediate medical attention
- Skin: Wash thoroughly with soap and water
- Ingestion: Do not induce vomiting, drink water, seek immediate medical attention
- Inhalation: Move to fresh air, seek medical attention if breathing difficulty
- Disconnect power before touching victim
- Call emergency services
- Begin CPR if qualified and necessary
- Emergency Services: TODO
- Poison Control: TODO
- Fire Department: TODO
- Inspect battery regularly for damage or swelling
- Monitor charging performance over time
- Replace batteries showing degradation
- Keep safety equipment accessible
- Stay informed about battery safety best practices
By building and using this kit, you acknowledge understanding these safety requirements and accept all associated risks.
If you have ANY doubts about safety, do not proceed.
Last Updated: TODO
Revision: See Revision Notes