Duracell is winning by a country mile in the race for dominance in the batteries market. But its performance is starting to stall. “It’s been in constant decline for the past two years due mainly to a falling unit rate of sales, as well as losing space on shelf,” says Nielsen client manager Julia Kaiser.

The top brand’s 1.3% value decline on units down 5.1% contrasts with the gains made by Energizer in the past year. With value up 10.9% on units up 4.6%, Energizer has managed to narrow the gap between the two brands by 15.1% to £48.4m.

“Alone, Energizer accounts for almost 80% of the category’s growth in the past year and is the only brand out of the top three that also managed to grow in units,” explains Kaiser.

Lower prices and larger packs have been key factors in Energizer’s surge, with the brand’s average price per pack over the past year standing at £4.42. Meanwhile, Duracell is a pricier offering at an average of £5.18 a pack.

Further down the field, bargain brand GP is making impressive inroads. GP attributes much of its growth to increased distribution and working more closely with its retail partners on merchandising and point of sale initiatives.

Meanwhile, Varta has fallen 17.1% to £174k despite pushing its rechargeable lines in a bid to attract environmentally conscious shoppers, as well as selling greater volumes in larger packs.

Battery sales are going, ahem, flat in the supers. They’ve sold 1.5 million fewer packs in the past year, a dip of 0.2%. Nevertheless, value sales are up 1.5% to £306.6m, thanks in part to growing sales of larger packs.

The standout performers here are online and the discounters. Lidl’s value sales are up 24.6% and Aldi’s are up 42.3%, albeit from a small base.

The big four’s performance is mixed, with Sainsbury’s and Morrisons in growth and Tesco and Asda in decline, by 1.3% and 8.1% respectively.

Bargain stores, which collectively account for 24% of the market, have seen sales fall 4.6%.

Commentators suggest this is because Energizer and Duracell are increasingly being sold in larger packs online and in the mainstream multiples, luring shoppers away from the cheaper offerings on sale in the pound stores.

Kantar’s read of the market suggests just 21.1% of sales have been on deal in the past year, a fall of 1.3%. This decline partly reflects the growth of discounters, which are less reliant on promotions, and the growing sales of packs with ‘x batteries free’.