Hand Warmers

Basics

• This page aims to go over the various forms of Hand Warmers, Existing Off The Shelf Options, and potential for OSE Improvements/Development

Disposable

• These are a bit wasteful
• Essentially Iron Powder and Charcoal/Some other materials to Moderate the Redox Reaction (Slow Hot Rust, rather than a Metal Fire etc)
• POTENTIALLY could be collected+reprocessed
• Also potentially could be made from or reprocessed with DRI as that process yields itself well to Powderization
• Alternative Chemistries would be interesting to pursue, but Disposable Devices (Short of Emergency/Expeditionary Use) don’t really fit OSE Specifications

Reusable

Rechargeable

Electric

• Essentially just a battery, resistive heating element, and control circuitry cleverly packaged together
• Main concern is Battery Life (long term, Charge/Discharge Cycles, ESPECIALLY thermal management)
• They do have the advantage of being easily recharged, and typically having long run times (10+ Hours)

Phase Change Materials

• Pretty Neat
• Also if clear they have a neat visual of the Supercooled solution recrystallizing
• Main downside is short runtime
• For better or for worse they are recharged via Boiling