Lithium AA(A) Batteries - Page 1
Forum section: electronics / general

author: Its wednesday my dudes
author_rank: Contributor
timestamp: August 18, 2023, 12:41:05 pm
content: Hi guys!some time ago I noticed that you now can buy lithium ion batteries in AAA, AA and 9V block form factors that actually deliver 1.5V (or 9V). I now plan to slowly preplace all my regular batteries to these after they run out. I started out with some AAA Kratax, which I had in use in my scale and later in my TV remote. But the endurance doesn't seem too overwhelming. So far I could't find a lot of reviews which are actually worth mentioning.This one works good an actual review:And this one to point out the ripple noise problem of the batteries:Before I proceed and spend more money (they are not exactely cheap) I would like to ask around if someone knows good reviews on this type of battery or maybe has himself a good amount of experience with them. Is there some kind of "goto brand" like Eneloop is for regular NiMH batteries?

author: Veteran68
author_rank: Frequent Contributor
timestamp: August 18, 2023, 01:13:25 pm
content: I recently boughtthis pack of four 9V Li-Ion batteries and a chargermainly for my DMMs that take 9V's (such as the Fluke 87V). When charged they are showing 8.5-9V, and so far are working well, but are still new so I can't yet speak to longevity or noise issues. That video makes me want to check the noise in mine though.I did a bit of research and review reading before trying these. If they work well I'll buy more. You can find supposedly >600mAH 9Vs but based on reviews they appear to be fake. These had good reviews overall.I know people like to say 9Vs aren't as prone to leakage, but I've had multiple cases of 9Vs leaking, including while still in the package. So I'm not taking chances with expensive gear. I have so many meters scattered around that with some of them it can be months or even years before I pick a particular one up. And when I do, I need it right then and don't want to have to partially disassemble it to install a battery. So the lithiums and Li-Ions have been mostly for my DMMs.I do have quite a collection of Eneloop NiMH AA's and AAA's, so far they've been serving me well so not yet looking for AA(A) Li-Ions. I did catch a good local sale recently on Energizer lithium AAAs and bought about 3 dozen, which I've mainly been using for DMMs, remotes, and other devices prone to leakage. I try to avoid using rechargeables in many of our household devices like TV remotes just because family members -- no matter how much I try to tell them -- are prone to tossing them out thinking they're disposable batteries. I use them extensively on my own stuff though, and will probably transition to rechargeable lithium chemistries as the tech improves.

author: Psi
author_rank: Super Contributor
timestamp: August 18, 2023, 01:21:39 pm
content: I've not looked into it, but I assume they have a 3.8V cell and a low quiescent current 1.5V regulator inside.So they're always draining the cell, even when the device is not being used. Unlike a normal AA

author: wraper
author_rank: Unknown
timestamp: August 18, 2023, 01:37:26 pm
content: Quote from: Psi on August 18, 2023, 01:21:39 pmNormal Alkaline and NiMH AA have self discharge too. The question how much it is. I doubt it's worse than non LSD (low self discharge) NiMH.

author: Psi
author_rank: Super Contributor
timestamp: August 18, 2023, 01:42:35 pm
content: Quote from: wraper on August 18, 2023, 01:37:26 pmTrue, but so do lithium cells.The lithium AA has its self discharge and the regulator current

author: KE5FX
author_rank: Super Contributor
timestamp: August 18, 2023, 05:22:51 pm
content: It's such a shame that the 3.7V AA form factor never caught on in anything except solar lights. I can't stomach the idea of a noisy buck converter in every AA cell in the house.

author: edpalmer42
author_rank: Super Contributor
timestamp: August 18, 2023, 05:50:35 pm
content: One issue with this type of battery is that the internal regulator keeps the voltage constant until the battery is exhausted. So there's no warning, like a dimming of the light, when the battery is almost dead. One brand (Jugee) drops the voltage from 1V5 to 1V1 when the battery is about 90% discharged. I don't know how well this works (I haven't bought any of these batteries - too expensive!), but I like the idea of the voltage drop.Ed

author: marhuum
author_rank: Contributor
timestamp: August 20, 2023, 04:05:02 pm
content: a cell : 3.7-4.2 Vwhere's 1.5 or 9 V nominal fromZDV divider, buck converter, charge pump, etc ?

author: Zoli
author_rank: Frequent Contributor
timestamp: August 20, 2023, 04:25:05 pm
content: I'm using non-rechargeable Li batteries for a few years, mostly AAA's. They last longer then the alkaline ones, and most importantly, never leaks. On the package the manufacturer claims 20 years of shelf life. Other thing to consider is the 1.8V voltage instead of the usual 1.5V.

author: Its wednesday my dudes
author_rank: Contributor
timestamp: August 24, 2023, 11:30:03 am
content: Ok, I've decided to return the batteries. While the idea seems nice, at least the AAA ones not even last for to weeks in my TV remote. I admit, it is a thirsty remote, but still, the first set of batteries it got delivered with, have lasted for serveral months. I will try Eneloops now and see how I fare with them.But I decided to give the 9 Volt batteries a try too in my multimeters. There are not so many alternatives anyway.

author: Its wednesday my dudes
author_rank: Contributor
timestamp: August 24, 2023, 12:49:28 pm
content: Ah, and I checked the voltage for the Kratax Batteries: They too seem to reduce the voltage to 1.1 V, when they're about to run out. But it seems, that this voltage is already to low for my remote.

author: tooki
author_rank: Super Contributor
timestamp: September 10, 2023, 05:54:18 pm
content: Quote from: Its wednesday my dudes on August 24, 2023, 12:49:28 pmI suspect that the issue is not the voltage, but the current. Infrared remote controls pulse their IR LEDs atveryhigh currents (1.5A — yes, amps! — is not uncommon). Alkaline batteries can easily supply this for a few ms even when fairly little capacity is left. The DC-DC converters in your batteries are relying on some small output caps, and they may not be up to the task when the battery is low.

author: bdunham7
author_rank: Super Contributor
timestamp: September 10, 2023, 07:04:00 pm
content: Quote from: Veteran68 on August 18, 2023, 01:13:25 pmAFAIK those are just two Li-ion cells in series with maybe some protective circuitry, so no noise in operation. They should read ~8.4V fully charged and ~7.0V when they're done, unless your device shuts off sooner. I use them in meters, voltage standards, fire alarms and so forth.