Can I buy an additional battery for the DC44?
If so, how much do they run?
yes.. and no.
the dc44 does not have a quick release for its battery.
if you're looking to buy a spare, it wouldn't be a quick swap if you wanted to use one while the other was charging.
you'd also need to buy an additional charger for your 'spare' battery, as the dc44' battery only stays topped off while connected to its charger.
however, if your dc44's original battery finally dies, you can most likely easily replace it. a replacement battery for the dc44 probably runs around $69.