Shanghai spot copper price chart January 13 18650 protected batteries have an electronic circuit.
The circuit is embedded in the cell packaging (battery casing) that protects the cell from [over charge", heat or [over discharge", over current and short circuit.
A 18650 protected battery is safer than an 18650 unprotected battery (less likely to overheat, burst or start on fire).
Batterie 18650, Battery Charger, CR123A Battery, 2032 Battery
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