What batteries cannot be used as replacements in other systems?

Certain batteries, like lithium-ion and lithium-polymer batteries, often cannot be used as replacements in other systems due to their specific chemistry and design requirements. Additionally, batteries with proprietary configurations, such as those found in certain electronics or electric vehicles, may have unique dimensions, connectors, or software integration that prevent interchangeability. Using an incompatible battery can lead to safety hazards, performance issues, or device damage. Always consult the manufacturer's specifications before attempting to replace batteries.