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This week, two rechargeable battery brands go head-to-head. One packs an electrifying amount of charge and is budget-friendly. The other, however, lost capacity quicker after a few cycles of use, lacking the stamina to go the distance.

At a glance: Ikea Ladda HR06 AA 1.2V 2450mAh vs Energizer Recharge Extreme AA

Best Buy: Ikea Ladda HR06 AA 1.2V 2450mAh

Average price in the past six months £9.80 | Cheapest price in the past six months £8

• We like: Exceptional battery life on a single charge
• Watch out for: Tends to leak a lot of energy when not in use

These batteries are Best Buys because they last so long on a single charge, at an impressive average of just under eight hours in a high-drain device. It took us 319 minutes – just over five hours – to charge them fully.

The capacity dwindles over time, losing about a third after 200 cycles. However, we’ve found that this is a fairly small drop compared with many other batteries on the market, and it doesn’t fall much at all until the 150-cycle mark.

Energizer Recharge Extreme AA

Average price in the past six months £15.15 | Cheapest price in the past six months £11.49

• We like: Gives you 7.5 hours of charge in a high-drain device
• Watch out for: Runs out of juice before 200 full cycles

This option from Energizer doesn’t quite live up to its name. It costs around the same price as the Ikea Ladda, but our tests found it rapidly conked out after 150 to 175 charges, which is below average compared to other high-capacity chargeables.

We also found the charge retention mediocre – they’re not great at keeping their charge when not in use. Overall, you’re better off choosing one of our Best Buys.

Our expert says:

'Rechargeable batteries can reduce your carbon footprint and save you a lot of money, especially if you find yourself churning through lots of disposable batteries. Our tests have shown the best can power devices for hours and can be reused hundreds of times before losing capacity.

'Ikea’s rechargeables are long lasting and don’t suffer from considerable capacity loss until around the 200 cycle mark. They easily compete and widely beat major battery brand alternatives and are comparatively cheap as well, making them a superb investment.

'Energizer is a big name in batteries, but its so-called ‘Extreme’ rechargeables are rather disappointing. Beyond solid battery life, there's not much to write home about. Plus, that battery life diminishes faster than many alternatives. 

Callum Pears, Which? rechargeable batteries expert