Where can I buy a replacement battery for the Electrolux Pronto 2-in-1

@spidey double check your model. The Pronto 2-in-1 should be a EL1000 not a HVEL. The batteries are not easy to find. Sometimes you can get them from places like this.

Also, this make and model had a recall on the batteries:"

WASHINGTON, D.C. - The U.S. Consumer Product Safety Commission, in cooperation with the firm named below, today announced a voluntary recall of the following consumer product. Consumers should stop using recalled products immediately unless otherwise instructed. It is illegal to resell or attempt to resell a recalled consumer product.

Name of product: Ergorapido, Pronto and Precision Vacuums

Units: About 320,000

Distributor: Electrolux Home Care Products Inc., of Bloomington, Ill.

Hazard: The vacuum's battery can expand and burst, posing a risk of injury to the user and bystanders.

Incidents/Injuries: Electrolux has received 34 reports of incidents in the U.S. involving damage to the vacuum and surrounding property. There have been two reports of minor injuries, including swollen hands and irritation to the eyes from contact with battery powder.

Description: This recall involves 2-in-1 cordless stick vacuums with a detachable hand vacuum and free-standing charger. Units involved in the recall have 9.6-volts printed on a serial plate on the underside of the handheld unit, and the following serial numbers: 074000001 through 085100001 and 74000001 through 85100001.

EL1000A - Pronto

EL1000B - Pronto

EL1000BX - Pronto

EL1000BZ - Pronto

PE1000B - Precision

EL1005A - Ergorapido

EL1006A - Ergorapido

So, be careful with the battery and make sure that you replace it with a safe one. Or you could comnsider rebuilding the one you have.