new agm and lead acid battery question

[hayfarmer]

bought a new battery for 4 wheeler ,   AGM type ES12BS  12V  dry. from walley world .60 bucks.and bought a

new LA battery ES4LBS  for a cycle  30 bucks .the LA  ES4LBS read 12.35 volts before adding acid.

and the AGM ES12BS read 12.90 volts before adding acid. the instructions said add acid wait 1 hour then charge 1-3 hours with a charger less than 2 amps per

hour which I did.My question is : why does the AGM type have a full charge before adding acid compared to the LA  type?

comments and explanation's gladly accepted.

Respected submitted

Hayfarmer

[zap]

The agm didn't have a "full" charge even though it showed 12.9v.  Without acid you'd never pull many (if any) amps out and the same after adding the acid but without charging it.

The agm most likely showed more voltage because the construction of the agm vs. flooded.  IIRC... dry charged agm are filled at the factory, charged, then drained.

[hayfarmer]

thanks zap,they ought to warn you that in the instructions, albeit they do tell you to charge it ,wonder how many assumed? thanks again for the info.

hayfarmer