'unchargeable' originates from the prefix 'un-' meaning 'not' and the word 'chargeable', which comes from 'charge', meaning 'to load or fill'.

'chargeable' evolved from the Old French word 'chargier', which meant 'to load or burden', and eventually became the modern English word 'charge'.

Initially, 'chargeable' meant 'capable of being loaded or filled', but over time it evolved to include the ability to be recharged, especially in the context of batteries.