Thankfully I’ve been doing a lot of work lately. And as a result, I’ve been going through a lot of 9v batteries. My Lectrosonics wireless units are quite good in terms of their battery life… I can get about six hours from a Duracell Procell alkaline battery. But running three units all day long, plus a pair for my Shure FP33 means that it’s tough to keep enough batteries on hand. I always like to have a spare unopened case with me, just in case… running out of batteries during a shoot is just not an option.
Unfortunately, most rechargables do not have enough energy density to be very useful on the set. I’ve tried some 9v NiMH, and they would only last 2 hours in the same application.
There is another option that is available from Trew and other dealers. A company called iPowerUS makes a 520 mAh 9v Lithium-Polymer battery. I had heard about these before, but a DP I worked with recently (Roger Herr, shooting Infested for Animal Planet/Darlow Smithson UK) actually had a set and recommended them, so I finally broke down and invested in a set.
I’m pleased to report that these are working great for me. I can get nearly an entire day in my wireless units from a single charge… even a little more by switching the power off between takes, so I’m not constantly changing batteries. iPower says their batteries will get over 200 charge cycles from each battery, and Trew reports this to be accurate… and in some cases, 200 cycles is a conservative estimate.
The downside is the initial cost… these batteries are initially quite expensive at $23 each in sets of four. (About $30 each with a charger.) But if we do a little math, they are really dirt cheap:
iPower- appx $30 each/200 charges = 30/200 = .15 per use
Procells- appx $20/12 (case)= 1.66 per use
These batteries break even after you’ve used six cases of 9-volts. (Or if you prefer, after being recharged about eleven times.) For me, that’s around 9 or 10 shooting days. These make sense if all you consider is dollars and cents. But more than that, it saves me time and grief not having to order a couple of cases of batteries every time I turn around. They charge in about 45 minutes, and the iPower charger comes with a 12-volt option for car charging… really handy. About the only downside I can think of is they don’t have a AA-sized solution for my Sound Devices gear.
So while it was a momentary pain in the wallet at purchase time, I’m really glad I bit the bullet and bought these batteries. So far, they’re quick, dependable, work great, and save quite a bit of cash and hassle over time.