Lightest AAA rechargeable batteries

There are no rechargeable lithium AAA batteries.

Well, not quite.

The standard energizer ultimate lithium batteries cannot be safely recharged. These batteries will explode.

There are Li-ion batteries, that are rechargeable in AAA size. However, they are not the same as the usual 1.5 V AAA battery, they are 3.6 V. And they are also less mah (~ 500) than the alkaline or energizer ultimate lithium. But, the higher voltage will also destroy devices not made for them.

Mostly in the AA size, flashlight nuts like to put these in their expensive lights so they can say "wow, look at the light", right before it burns out.

When it comes to weight, and energy content, for normal devices the energizer ultimate lithiums cannot be beat, they are are tops. There are very high drain devices where rechargeables with much higher output capacity would be superior. For instance, a real AA NiCd or NiMH battery can put out 20 amps if needed, waaaaaayyyyy more than an alkaline or ultimate Li. Enough to start fires , which is why regular consumer batteries are pretty timid and relatively safe.

If someone was asking if you can fill your car with water instead of gas , my answer would be "no you cannot" however someone could argue that you can.

The Li Ion (rechargeable)3.7v batteries that have the same size as the AAA are called 1044 NOT AAA specifically so that people don't hopefuly put them in the wrong device.

The AAA lithium are lithium iron disulphide (1.5-1.7v) , disposable not rechargeable.

I see. So no lithium rechargeables then.

What about the lightest rechargeable AAA battery then?

Eneloop rechargeable high capacity NiMh are pretty good http://www.amazon.com/Panasonic-BK-4HCCA4BA-Pre-Charged-Rechargeable-Batteries/dp/B00JHKSL0A/ref=sr_1_7?s=electronics&ie=UTF8&qid=1403146663&sr=1-7&keywords=aaa+nimh+eneloop

I've used the AA version quite a bit. Pretty good capacity for the weight. Recharges many times.

Other NiMh are good too, but those ones might be better

And don't get the regular Eneloop, although they're almost as good

another thing about NiMh is they have a slow discharge. You want to charge them within a week or a month of using them. I think that one version is a little better that way though.

I have seen weights between 13 and 15g each for the NiMH type.
I just tried 3 different brands (750 to 800 mAh), 2 batt each, they all registered 25g on my scale. (rounds off to the nearest 5g)
I think that once you compare amperage with weight you will end up with pretty much the same result.
The disposable lithium are about half of that weight.
BTW, yes the Eneloop would make more sense (than other NiMH) because of the low discarge rate and they work in lower temps than the other rechargeable, p[articularly the Pro.
I have used AA and AAA Eneloop std (white) for several years, same sets, they still work.

The high capacity Eneloops are 950 mAh. They're black with these X symbols. Relatively new version.

I think all NiMh weigh the same.

When it comes to rechargeables, weight is proportional to capacity.
If you dont believe this, go buy the cheapest chinese rechargeable you can find and experience it first hand.

The energizer ultimate lithium AAA L92 will give about 1200mah, 50% more than the alkaline or NiMH batteries and is much lighter as well. Lets say that again, about 50% more useable power, and is THE LIGHTEST option.

All rechargeables, suck, unless used often. NiMH suffer the same problems as NiCd did, despite hype to the contrary, albeit to a lesser extent. Let them go dead and they are toast. They also lose capacity over time.

I use NiMh AA in GPS. They do at least 20 recharge cycles. Then I start noticing their capacity is a little less. Especially if it's real cold.

Yeah, non rechargeable Lithiums are better. 20 AAAs for $30 from Amazon isn't too bad. 20 AAs for $35. They have a slightly higher voltage which some devices don't like. A good choice.

Regular Eneloops will take MANY more charges than the newer XXX high capacity ones. In the end, I find them more than sufficient for my lights and GPS and want the bang for the buck. IMO, the extra capacity is negligible, compared to the much longer life of the regular Eneloops.

Weight
As capacity increases weight does too but not proportionally so.
For example for Panasonic/Sanyo in AA :
Eneloop Lite are 19g , 950 mAh
Eneloop 27g , 1900 mAh
Eneloop Pro 30g , 2450 mAh

so comparing the Lite with the Pro, for 57% extra weight you get 2.5x the power
( I am quoting the "minimum power" not the slightly higher avg power)

ahhh… no such thing as free lunch?

regular eneloop AA – 2000 mAh
high capacity – 2550 mAh

I've been using high capacity in my GPS for almost 2 years. 20 cycles of mostly discharging and then recharging. I haven't noticed any signs of reduced capacity yet.

So, for me, the fact they don't have as many discharge cycles isn't important. Maybe I have to replace every few years. Regular eneloops would last a few years longer than that?

It's been at least alluded to here – but what are you planning on using the AAAs in?

I'd weigh options against my intended use. If it's for a headlamp and maybe a backup AAA flashlight for around camp use – i.e. you don't need a lot of output – regular Eneloops are hard to beat. Proven and reliable. 2000mah capacity will not be an issue for normal use.

If you're looking for a higher drain device – GPS perhaps or digital camera – the higher mah may work better and be worth using.

If you're looking for a brighter flashlight get a AA or 123 based light anyway – AAA lights don't have the mass for super output anyway for any appreciable time – one reason I don't have any 10440 based lights, they aren't terribly practical.

I hope rechargeable Lithium-Polymer batteries in AA and AAA soon hit the market.

Li-polymer batteries are lighter than Li-Ion and can take more recharge cycles. Some of the better hybrids and all-electric cars like the Tesla now use Li-polymer batteries but they are 'spensive.

That's why Toyota is not sure if their 3rd gen Prius coming out in 2015 will have them or they will stay with Li-Ion like my 2013 Prius V has.

Same problem. wrong voltage for AA.
Somehow folk have a problem understanding that AA and AAA is not just a size it is about voltage too, around 1.5v.
In fact some AA devices don't work or don't work correctly using Li Ion at 1.7v so how are they going to work at 2.7 v?
Lithim Polymer produces 2.7 to 3v so it cannot be used on devices designed to work with a AA or AAA battery.

Some devices, all actually devices, have an operating voltage range. Some narrower than others. I have a gps that will not work with rechargeables , it requires 1.5V, 1.2-1.4V doesnt cut it. Wish I had known that before I bought it.

Many high end flashlights accept 1.2-3.6 V batteries, meaning that they can take the Li-ion. The LED life and circuit board life is shortened due to heat usually. For instance, zebralight H52 can take the 3.7V Li battery.

"Battery: One 1.5V AA (NiMH, lithium or alkaline) or 3.7V 14500 li-ion rechargeable."

Yes we have done this before with the AA…
The devices that can take both AA 1.5v and 14500 3.7 v batteries are very few, in fact I know of some lights and nothing else that applies to hiking.
The problem here is that someone could read about those 3.7v batteries and assume they will work in their camera or GPS or headlight only to find out in the field that they don't. This could be at best inconvenient at worst… well you could work this out. (GPS without maps situation..)