When working abroad for long periods, it is not only better for the planet to be using rechargeable batteries but often more practical. The environmental implications of taking weeks’ worth of disposable batteries with you on location are obvious; you are creating a great deal of toxic waste in places where battery recycling points are often few and far between, if not non-existent.
Using rechargeable batteries also has practical advantages. The ease of carrying a small pack of rechargeable batteries (and perhaps a pack of disposables for back up) means you have lighter luggage, reducing airline costs and carbon emissions . You should also never run out (provided you have power to recharge)! Certain brands of radio mic (eg Zaxcom, Wisycoms) have a battery meter on the receiver (in the recordists bag) which shows how much battery charge is left in the transmitter (on the talent) so you can keep on top of when to change batteries and shouldn’t get caught out.
There are some negatives to rechargeable batteries. Recharging may not always be possible if you are in a remote location with unreliable or non-existent mains power, hence the need to carry some back up AAs with you. Rechargeable batteries in radio mics might need changing more often than disposables, every 3-4 hours depending on the transmitter power setting, so compared to using industrial Duracell disposable AAs, which last all day, you have to be more on the ball. Even though rechargeables may not last as long, when there is a break in filming you can automatically change the battery even if it is half charged and you don’t lose anything, compared with throwing away a half used disposable.

Good quality batteries and chargers are not cheap. However when you weigh up the cost of going through disposable batteries which are replaced every day, it makes more economical sense to have one product that you can use again and again. The key to rechargeable batteries is being organised, having a system and knowing which batteries need charging and which are ready to use. Many sound recordists do this by using a caddy, with used batteries pointing up and unused pointing down.

Ellie Williams is a Sound Recordist based in Bristol who specialises in wildlife shoots in remote locations. With a background in production at the BBC’s Natural History Unit, Ellie is very environmentally aware. She uses rechargeable batteries for all her sound kit (even her head torch) and has given us her recommendations of the best batteries in the technical information below.

Technical Info

• I use NP batteries in my bag (that I carry on my front) and then 2 x rechargeable AAs for each radio mic transmitter (that are at the presenter/contributor end). I need to change AA batteries roughly twice a day and NPs once a day for Natural History sync shoots using rechargeables. NPs are big rechargeable batteries that sit in a ‘shoe’ which is a little device that slots on the end and has lots of sockets on it for you to plug in everything you need. It works a bit like a gang plug adaptor. They’re brilliant and are standard kit among recordists. NPs show when they are running low with a button on the side. The one I use powers five different bits of kit at the same time – everything in my sound bag. It lasts a whole day and charges in a couple of hours. This is much less of a worry than if everything was powered by AAs and you had to keep an eye on the power left in each device. The shoe that they go into has on and off switches so you can turn everything off super quickly to save power during breaks. They’re amazing!

• Eneloop Pro AAs for the radio mics and an Ikea alternative (Ladda) which is made in the Eneloop factory and lasts just as long but is much cheaper.

• Battery suppliers H-Squared recommend the Duracell 2500mah Nickel Metal Hydride (NiMH) rechargeable AA batteries. They’re a trusted brand because they’ve been produced for a long time – they have good data on their performance. They’re roughly half the price of the Eneloop Pros. • Disposable AAs: Duracell Energizer Industrial AAs are the best disposable brand for lasting all day.

• Chargers: The intelligent ones (more expensive) give you peace of mind as they show you exactly how charged the batteries are. I know that my current production wouldn’t want me to use anything less accurate.

• Battery suppliers H-Squared recommend the Maha C9000 charger because it has an ‘intelligent’ display and has a cigarette lighter charging adapter so can be used in vehicles as well as universal adapters for overseas mains use, saving you the cost of buying additional adapters. They should last for 10-15 years and have a 2 year warranty.