Speedlite 600ex-rt battery problem

[PhotoSmurf]

Hi

I have just bought a 600ex-rt ... But the batteries I put in it (which are all new) only result in a "replace battery" sign and the flash refuses to switch on.

I have tried 3 new sets of batteries, all are top grade lithium batteries, is there a known issue with lithium batteries - the manual says they can be used?

Many thanks for any info that could help.

[Stephen]

Hi, MichaelD.

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[nomadphoto]

Remove the SCH-E1 from the top of the flash. It's the clear, whitish plastic piece on top of your flash located where the light comes out. The back should say, Made in Japan (in black) and below that, SCH-E1. Take off the SCH-E1 from the unit, open the battery department door, place new batteries into the battery department, close the battery lid, and turn on the flash. If that doesn't work, also try cleaning your battery department connectors located behind the little door. 

[nomadphoto]

take off the gel filter, place in the new batteries, turn on the flash. it worked for me, hopefully it works for you too. good luck.

[butchdon]

I was on number 8.

Thanks

[Kat65]

Hey flash, you’re an absolute legend. You dropped this advice in 2014, and 8 years later it still holds! Had almost given up on this second hand speedlite I bought but came across this advice and IT WORKED! Thanks so much!

[Flash_Speednite]

Thanks. I'm glad it's still providing use. Doesn't seem like that long ago. 😉

[normadel]

Regarding use of Lithium batteries in Canon Speedlite: Here is a Service Notice issued by Canon in 2019:

******************************************************************************************************************************

"Service Notice: Caution Concerning use of Lithium Batteries

Update

Thank you for using Canon products.

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

Details

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."

*********************************************************************************************************************************

Apparently, Canon Canon doesn't want you to use Lithiums, and I have read independent articles which discuss AA battery types and warn, in greater depth,  against using Lithiums in flashes. Here is an excerpt from one:

**********************************************************************************************************************************"Lithium AA batteries Lithium/Iron Disulfide (Li/FeS₂). These 1.5 volts and are
NOT the same as the Lithium ion batteries used in cameras. These work well, and
with some advantages, except they are not rechargeable, and will recycle more slowly
than any of the others. Energizer Ultimate Lithium AA Batteries (8-Pack) can provide
more flashes than the others. Better life than alkalines at high current loads (flash
units), and much better performance than any in extreme cold temperatures (to -
40°C per Energizer data sheet — this is what you want in sub-freezing temperatures).
Even the weight is lighter. Shelf life is 20 years. A bit more pricey, but better in a few
ways except for recycle time and heating concerns (and of course replacement
cost). Recycle time is important for speedlights, but these lithium cells contain
protection to limit the maximum current for safety reasons (heat).
Note that this above is now a new improved AA Lithium battery, which limits the
current less, better and faster recycle. Those I saw recycled faster, at least at same
speed as alkalines in flashes now. If using a lithium AA, flashes will want the new one
called Ultimate. But these cells start out at 1.6 volts. Be very aware of heating
conditions (fast shooting speed makes it worse). In fact, Canon put out an advisory
stating: Do Not Use AA Lithium Batteries in a Flash.
If shooting rapid flash shots, the lithiums can get especially hot, especially fast, and
could damage the flash, and may just quit (thermal fuse). A single flash only every
now and then is one thing, but any rapid shooting is surely better off with NiMH (but
rapid is always a concern to a flash). The lithium flash recycle times are longer too,
which is a biggie when waiting for the next shot. Eneloop NiMH rechargeables remain
my own choice for my speedlight use.
The previous data sheet (older battery named "Advanced") previously said they limit
current to 2 amps for pulse loads, to prevent hazard. The current new L91 data sheet
(battery named "Ultimate") now says only limited to 2.5 amps continuous, or 4 amps
maximum peak (2 seconds On, 8 seconds Off), with less internal resistance, and
seems as fast as Alkaline now, and will last longer than alkaline in flashes. The
lithium high internal resistance was artificially added as a safety factor. See their
Application manual page 19-20 for reference of this safety protection (It says L91, but
both were L91, each in their time. This document dated 2001 is the older version).
Flash wants the new version called "Ultimate".
These AA size lithium are NOT rechargeable. Lithium rechargeables are not AA size,
because lithium rechargeables are about 3.3 volts instead of 1.5 volts for AA (lithium
ion for cameras and laptops are a different chemistry. 3.6 volts per cell). The big
point is, lithium rechargables are NOT 1.5 volts. Lithium AA cells are instead Li/FeS2
chemistry."
***********************************************************************************************************************************

[lbow]

I'm also having a similar issue. The unit is about 3 years old, and I don't use it that often. It's been fine until today. I turned it on, and...no power. I changed the batteries, twice. Still no power (not even and icon on the screen, nothing. A complete mystery and VERY frustrating!

[lbow]

I'm also having a similar issue. The unit is about 3 years old, and I don't use it that often. It's been fine until today. I turned it on, and...no power. I changed the batteries, twice. Still no power (not even and icon on the screen, nothing. A complete mystery and VERY frustrating!

[lbow]

This actually worked! Very weird solution, but thank you!