Any H2S you are likely to encounter will be around drilling rigs. H2S is a product of certain organisms that live well underground or in oceans. H2S makes batteries, but batteries don't make H2S :)
As mchannon noted, batteries produce H2 gas. Googling "lead acid redox cycle" will provide multiple explanations.
As mchannon noted, batteries produce H2 gas. Googling "lead acid redox cycle" will provide multiple explanations.