NEW YORK (AP) â¿¿ ___ Holiday discounts crimp retailers' profits NEW YORK (AP) â¿¿ The 2011 holiday shopping season will go down in the record books as the year the Grinch stole stores' profits. Many retailers sacrificed their bottom lines by pushing heavy discounts to shoppers bent on getting a good deal in a challenging economy. That created a sharp divide between stores that won the battle for wallets, and those that didn't. The big winners? Shoppers who held out for deals late in the season. Retailers collectively reported a 3.5 percent increase in revenue at stores open at least a year for December, according to a tally of 25 merchants compiled by the International Council of Shopping Centers. For November and December combined, the figure rose 3.3 percent, a solid increase but smaller than last year's 3.8 percent rise. ___ GM to add more steel to Volt to protect battery DETROIT (AP) â¿¿ General Motors is advising Volt owners to return their electric cars to dealers for repairs that will lower the risk of battery fires. The company hopes adding steel to the plates protecting the batteries will ease worries about the cars' safety. Three Volt batteries caught fire after government crash tests last year, prompting a federal investigation and sending GM engineers scrambling for a fix. Eligible for the fix announced Thursday are 8,000 Volts on U.S. roads and another 4,400 still for sale. The repairs are covered under a "customer service campaign" run by GM, which is similar to a safety recall but allows the carmaker to avoid the bad publicity and federal monitoring that come with a recall. ___ Euro jitters back amid bank woes, French bond sale PARIS (AP) â¿¿ The specter of Europe's debt crisis returned Thursday as bank stocks fell sharply on worries about losses on government debt and a French bond auction dampened investor demand.