Do Not Use Lithium Batteries in Speedlites—New Canon Advisory

By Sly Arena On February 25, 2015

While updating the information in my chapter on batteries for the new addition of Speedliter's Handbook I came upon a relatively new service advisory from Canon (December 2014) that advises against the use of lithium batteries in virtually all Speedlites. Canon acknowledges that lithium batteries may become extremely hot when used in Speedlites.

This should be considered breaking news for Speedliters. I checked the user manuals for the last five Speedlite introductions and they all say that lithium batteries can be used in the Speedlite.

I said a long while back that lithium batteries are bad for Speedlites. Five years ago, when I wrote about my AA Battery Torture Test in the original Speedliter’s Handbook, I reported three disturbing facts about the performance of lithium batteries during the test.

• When a 580EX Speedlite with lithium batteries was fired at full power every 20-seconds (the standard interval in my AA Battery Torture Test), the average flashes-to-failure was 52 pops. This compares to averages of 165 for alkaline and 235 for low-discharge nickel-metal hydride batteries, like Eneloops.

• When the Speedlite with lithium batteries was fired at full power every 3-minutes, the average flash-to-failure rose to 218. It’s not that the lithiums lacked the electrons. Rather, they just like to hold onto them—which is why they can hold a charge for many years.

• Most importantly—under the standard 20-second test interval, the sets of lithium batteries would be too hot to hold immediately after the test—on the high side of 140ºF/60ºC.

Recommended Batteries For Speedlites

My favorite batteries for Speedlites are Eneloops. They are low-discharge rechargeables. Low-discharge is the key. Regular nickel-metal hydride batteries will lose most of their charge while sitting for a month in your bag. The low-discharge chemistry in Eneloops holds onto most of its charge for up to a year.

The key to happiness with rechargeable batteries is the circuity of the charger. You need a charger that treats each cell as an individual. Otherwise, the charger will turn off when the strongest cell is charged—leaving the weak cells undercharged. My favorite charger is the Maha C801D.

Text Of The Canon Advisory

AA Lithium batteries cannot be used with any Speedlite or Macrolite products and compact battery packs including those listed below because certain AA lithium batteries, in rare cases, may become extremely hot during usage in such products.

Speedlite 220EX
Speedlite 270EX
Speedlite 270EX II
Speedlite 320EX
Speedlite 380EX
Speedlite 420EX
Speedlite 430EX
Speedlite 430EX II
Speedlite 540EZ
Speedlite 550EX
Speedlite 580EX
Speedlite 580EX II
Speedlite 600EX
Speedlite 600EX-RT
Macro Ring Lite MR-14EX
Macro Ring Lite MR-14EX II
Macro Twin Lite MT-24EX
Compact Battery Pack CP-E2
Compact Battery Pack CP-E3
Compact Battery Pack CP-E4

It is my belief that this holds true for most contemporary flashes.