If you’re putting up Christmas decorations this week, don’t forget to check your batteries. Our tough Which? battery tests reveal the best batteries to keep your fairy lights shining through the festive season.
The best AA disposable batteries power devices such as fairy lights for over 11 hours longer than the worst, according to our latest disposable batteries test results.
So the worst batteries in our test could fail Christmas morning, whereas the best will still have your fairy lights twinkling until after everyone’s polished off their Christmas dinner.
We’ve tested disposable batteries from Duracell, Energizer, Varta as well as supermarket own-brand alternatives.
Best batteries test for fairy lights
Which? disposable batteries tests simulate the types of devices you use your batteries in, so you know which will last the longest when you get them home. Our medium-drain test is a good indicator for fairy lights and other battery-powered lighting, such as garden lamps or bike lights.
High-drain tests show how long batteries last in your most power-hungry devices, such as remote control toys or model aeroplanes. One of the most common uses of batteries is in clocks and clock-radios, so our low-drain test replicates the kind of conditions found in these devices.
So before you buy any batteries for Christmas, check our batteries test results first.
Best rechargeable batteries for Christmas
If you have several battery-powered festive decorations – plus a few new toys or gadgets come Christmas morning – it’s worth considering rechargeable batteries.
The initial cost of a charger plus batteries can seem significant compared with a few packs of disposables, but some big brands claim their batteries can be recharged up to 300 times. Buying the equivalent number of AA disposable batteries would cost you between £75 and £525.
We test rechargeable batteries too and find big differences between the best and worst. The best AA rechargeable batteries will keep the most power-hungry devices running for at least seven hours, while the worst manage four hours.
It’s also important that rechargeable batteries hold their charge well between uses so that you don’t find your cells are empty when you want to use them. So we test this too: the worst battery we’ve found leaked away 38% of its charge when not used for 50 days.