Test / Review: Energizer Ultimate Lithium AA

Energizer Ultimate Lithium AA

Official specifications (The second part of the specification is from datasheet):

  • Last up to 9x longer in digital cameras (versus Energizer® MAX®. results vary by camera.), which means 9x less waste
  • Weigh 1/3 less than standard alkaline batteries
  • Perform in extreme temperatures from -40°F to 140°F
  • Hold power for 15 years when not in use
  • Leak resistant construction
  • Classification: "Cylindrical Lithium"
  • Chemical System: Lithium/Iron Disulfide (Li/FeS2)
  • Designation: ANSI 15-LF, IEC-FR6
  • Nominal Voltage: 1.5 Volts
  • Storage Temp: -40°C to 60°C (-40°F to 140°F)
  • Operating Temp: -40°C to 60°C (-40°F to 140°F)
  • Typical Weight: 14.5 grams (0.5 oz.)
  • Typical Volume: 8.0 cubic centimeters (0.5 cubic inch)
  • Max Discharge: 3.0 Amps Continuous (single battery only) 5.0 Amps Pulse (2 sec on / 8 sec off)
  • Max Rev Current: 2 uA
  • Typical Li Content: Less than 1 gram
  • Typical IR: 90 to 160 milliohms (depending on method)
  • Shelf Life: 15 years at 21°C

This battery handles load very well. Notice that the unloaded voltage for lithium batteries is 1.8 volt.

I am not that impressed with the 11x longer specification, you must compare to some really bad batteries for this to be true.

Up to 1A the capacity is nearly constant and even at 3A it can deliver energy.
The 3A curve starts with a dip, then it raises again, when the battery gets warm.

Due to the higher voltage, it has more energy than alkaline.


This battery is very impressive at high current, but at low loads it is not much better than alkaline batteries (Except it does not leak). The batteries have a very long storage time and can be used in very cold weather.
These batteries cannot always replace alkaline, some equipment depends on the weak high current ability of alkaline!

Notes and links

How is the test done and how to read the charts
Comparison of AA battery chemistries

Excellant review!

Thanks for pointing out that these are not any better than alkalines at low currents, except that they don’t leak.

They are not much better. They have higher voltage and slightly higher capacity at low current.

I did forget to include that in really cold weather, they are much better.

Oh right, these are much better at colder temps, forgot about that as well. :slight_smile:

All my high current AA applications are handled by Eneloops and low current ones by alkalines, so I guess these don’t fill a big niche.

I do like to take this apart and have fun with the lithium inside. (Don’t try this!)

I keep a big supply of these .

You never know ...

These battery reviews are nice :slight_smile:
It would be cool if you could combine few of the discharge curves of Alkaline, NiMH and Lithium into one for easy comparison.

Here you go:

Source: http://lygte-info.dk/info/ComparisonOfAABatteryChemistry%20UK.html

Oh, thanks! I found this one interesting too:

I’m confused by depending on weak high current of alkalines

These AA Li-ion primary cells are also known in the trade as Energizer Ultimate L91 AA
(check carefully for a tiny ’L91” printed sideways on the mid-cell in the fourth battery picture from the top post).

Confusingly, Energizer is also marketing a cheaper range of look-alike cylindrical, lower mAH capacity,
1.5V primary Li-ion batteries, known as Energizer Advanced Lithium.

Summary of current Energizer Li-ion cylindrical 1.5V primary (throw-away) battery line-up:

Energizer Advanced - EA91 - AA - max discharge 1.5 A continuous
Energizer Advanced - EA92 - AAA - max discharge 1.0 A continuous

Energizer Ultimate - L91 - AA - max discharge 3.0 A continuous (as reviewed here)
Energizer Ultimate - L92 - AAA -max discharge 1.5 A continuous

Mfr Data sheets:




I’ve tried them against the Chinese “Nice” brand lithium primaries (from FT at about $1 a pop) and for the life of me, I can’t see a lick of difference. I wouldn’t be a bit surprised if they’re the same battery with a different wrapper.

I keep a good stash of them as well. I hate alkyleakers. Eneloops or lithium primaries for me, please.

Some lights depends on the batteries limiting the current. Lithium batteries has higher voltage than both alkaline and NiMH, even at 1A.

Thanks again for great review HKJ!

I wish more companies made lithium primaries in AA and AAA, is this because Energizer has a patent?

Yeah in things like tv remotes and clocks, these aren’t worth it over alkalines.
But for our lights these things are awesome.

That’s interesting, do those Fasttech ones have expiration dates similar to these lithiums?
I wonder if they are old batches?

how do they limit the current?

No, the “Nice” lithium batteries only have manufacturing date printed on them. They are also physically little different so they are completely different product from the Energizers.

The last batch I got show what appears to be a manufacturing date of Mar. 2013, with the comment “Period of validity 15 years”….“Guangzhou Nice Battery Tech Co Ltd.” They just came in shrink wrapped pairs. I bought both AAs and AAAs - both seem to have run times identical to the Ultimate Lithium cells we get here for a whole lot more money.

Look at the curves for alkaline, when drawing more current the voltage will drop more.

Thanks HKJ. The eleven year life span look impressive. I wonder if different temperatures affects this?

Varta, GP, Camelion, Ansmann, Raver, Philips