It occurred to me that in recent posts I’ve talked about what kind of rechargeable batteries to use, how to charge them, and how to store them, but I haven’t actually talked very much about WHY you should use them. I’ll do that now!

This might be obvious to some of you, but for others it’s a pretty hard sell when they see price tags of $10-20 for a set of 4 AA or AAA NiMH rechargeable batteries (I prefer Sanyo Eneloop batteries) when you can buy a huge box of alkaline batteries for less (here’s a box of 48 AA’s for only 6).

Here are 3 reasons why you should use rechargeable batteries in all your electronic gadgets and camera equipment, especially in your Speedlite flashes:

1. Better for the Environment: Millions and millions of batteries get disposed of every year and most of them go into landfills. They all contain heavy metals and they really aren’t very good for the environment. Even when recycled they take lots of additional energy to reprocess, which is simply wasteful when their are excellent rechargeable alternatives available.
2. Cheaper in the Long Run: although alkaline batteries are relatively cheap to purchase, you can reuse your rechargeable batteries hundreds of times and they quickly pay for themselves. For the full time pro or the advanced amateur this is probably a no-brainer. But it’s still true even for a beginning photographer. If you use a Speedlight Flash that takes 4 AA batteries, I’m willing to bet that you have to replace your alkaline batteries at least once a month, and maybe even more often if you use it a lot (even spectators at a wedding often can’t make it through an entire event on one set of batteries). So even if you only replace your batteries 12 times per year, a set of 4 Eneloops for $13 is already cheaper than that big box of alkalines for $16, and you can save even more by buying the rechargeables in bulk packs. If you are using 2 or 3 flashes plus a few other electronic gadgets that use AA batteries these savings multiply (and you can share your spare batteries amongst all the devices!).
3. Better Performance: I find that NiMH batteries recycle my flashes faster and last longer than alkaline batteries. This is counter-intuitive since rechargeables are typically only 1.2v vs. 1.5v for alkalines, but they are different technology and it really is true. You may find that alkaline batteries work better than NiMH’s when they are both fresh, but that alkalines drop off very quickly. I find that NiMH’s continue to perform very well until they simply stop working; alkalines work well initially but then performance quickly drops off to the point where it might take 10 seconds to recycle a flash (compared to 3-4 initially). This was honestly the main reason that I switched in the first place, but in retrospect the other reasons are just as important.

Note – if you haven’t read it yet, you really owe it to yourself to read my earlier article about Better Rechargeable Batteries before you actually buy any NiMH batteries. They are not all created equally…

Most photographers have several sets of rechargeable batteries; typically at least two sets for each of their portable flashes (or other gadgets or cameras that use AA or AAA batteries). This becomes a management issue because they bang around inside the bottom of the camera bag and it’s difficult to know which batteries are charged and which ones are dead.

I have an easy two-part solution:

1. Organize Your Batteries in Sets: These clear plastic cases for AA batteries are perfect for keeping rechargeable batteries organized into sets. At less than $2 each they are very inexpensive, and since most electronic devices use batteries in sets of 2 or 4, they hold just the right number of cells. They are also available for AAA batteries and in larger sizes in case you want to hold more than 4 batteries.
2. Carefully Arrange the Batteries in the Case: Most devices that use AA or AAA batteries must be loaded so that the orientation of the positive and negative terminals for adjacent cells alternate. If you always load your cases with freshly charged batteries so that all 4 cells are oriented in the same direction, and load cases with dead batteries alternating, you can tell with a quick glance whether each case holds fresh or dead batteries.

As a followup to my previous article about Better Rechargeable Batteries I wanted to discuss the other half of the battery life issue. This is the charger. Another simple truth is that there are chargers, and then there are chargers.

The charger that came with your batteries is most likely a simply unit the plugs directly into the wall. It probably charges four AA or AAA batteries at a time, and most likely requires batteries to be loaded in pairs. It also very likely charges your batteries quickly. Very quickly. Like in 15 to 30 minutes, and the probably come out smoking hot!

There are some advantages to this type of charger; they’re small, lightweight, and very cheap. They’re easy to pack for travel and they allow a very quick turnaround time so you can get your batteries back in service quickly. I have one of these chargers and I take it with me whenever I travel.

To my mind, the main disadvantage to this charger is that charging batteries quickly (and very hot) is known to reduce their lifespan, and it also prevents them from reaching full capacity. If this is the only charger you ever use your batteries will not last very long (in terms of total number of cycles) and they will never reach their full potential (in terms of total capacity per charge).

Although better chargers, such as the Maha Powerex MH-C800S or the La Crosse BC-700, are much more expensive (typically $40 to $100), they have several huge advantages:

• Up to eight independent charging slots that accept any combination of AA or AAA batteries. Batteries are charged individually rather than in pairs. This is great if you have devices that use odd numbers of batteries, such as 1 or 3.
• Smart electronics that charge each battery independently without over or under-charging.
• LCD Display that shows the status of each individual cell.
• Deep conditioning charging cycle to restore failing batteries and reduces or eliminates any memory effect.
• Choice of soft (1-2 hours) or rapid (2-4 hours) charging speeds.

Before I got my MH-C800S charger my batteries failed regularly. I had many “dead” batteries that either wouldn’t take a charge at all, or that had such a large memory effect that they were unusable in my Speedlite Flashes. Since I bought it (about 3 years ago) I have never had to replace a set of batteries. I have certainly bought additional batteries in that time, but every battery I have ever put through this charger is still running strong today. I was even able to use this charger to bring some previously “dead” batteries back to life. I am extremely happy with it and I think you will be too.

Note that there are many other similarly advanced chargers on the market, but every Maha / Powerex or La Crosse charger that I’ve ever seen a review for was highly praised, so I would recommend that you stick with these manufacturers.

Check them out and be sure to get something better than the default charger that you got for free with your batteries. You won’t be sorry.

I get questions all the time from people using NiMH Rechargeable Batteries that don’t last very long or that don’t seem to put out full power. The obvious question is whether there is something is wrong with the batteries, the charger, or both. These batteries are pretty expensive and it can be really annoying when they don’t do the job they are needed for.

Unfortunately, rechargeable batteries continually lose some of their power in a process called self-discharge. This process occurs at different rates in every type of battery, and it occurs very quickly in standard NiMH batteries. In my experience they only hold enough charge for a few days before the reduced charge levels becomes obvious. When I try to use them in my Speedlite flashes I find that I really have to charge them the same day, or maybe the night before, if i want to get decent life out of them.

If you need your batteries to last longer then you need to get low self-discharge batteries (often marketed as Pre-Charged batteries), such as Sanyo Eneloops. I find that these batteries, even at only 2000 mAh, last far longer and are much more useful than any of my 2500 – 2900 mAh standard NiMH batteries. I now have enough of these batteries for use in all of my flashes plus a spare set for each flash as well. You can leave these in your camera bag for months and they only lose a small percentage of their power.

For more information and to learn about other brands of batteries, check out the Low Self Discharge NiMH Battery article over at Wikipedia.