Stop using Alkaline Batteries and use newer rechargable NiMH or Li-ion instead

[Daley]

A few days ago, scruffy YouTube electronics repair/maker dude Big Clive from over in the UK posted an interesting video that left me chewing on the subject and changing my approach to batteries.

Video here: The curse of leaky alkaline batteries

I had no idea that NiMH battery technology had progressed to the point that it has. You can now get low discharge high capacity NiMH batteries for relatively cheap, all things considered. I'd known of Eneloops in the past, but those are still too pricey for our means. A couple years ago, we had stopped using alkaline 9V batteries with our TENS machine due to the cost, and had good luck with EBL NiMH batteries over at Amazon. The 9 volt batteries got the job done, and kept a fair charge even sitting for a while, but at the time, the 1.2V AA/AAAs were still considered dodgy. Apparently, no more!

Edit: For those with power sensitive devices where the 1.2V out of a NiMH battery is a non-starter, look into newer 1.5V Li-ion rechargeable batteries instead. They're more expensive, but the ROI can still come in under ten years under certain use cases, which is considered perfectly acceptable in this community. There's more on this in later posts, but know that within the past two years, manufacturers have finally figured out how to put a decent sized 3.7V Li-ion battery in a AA/AAA form factor, along with the circuitry needed for safely charging and voltage limiting discharge to 1.5V. Storage capacities come close to the current highest end NiMH options, and voltage outputs are high enough to not cause issues with power sensitive devices. Needless to say, the rechargeable AA/AAA batteries of the early 2020's due to storage capacity, idle discharge limiting, and power output are nothing like the rechargeables that we've seen even five years ago... which is a good thing given how cheap and trashy the off the shelf alkalines have gotten these days.

The interesting thing is, I'd just found a damaged Maglite and camping light that I'm gonna have to repair a few weeks back from leaky alkalines, so the thought was fresh in my mind about how much I hated how the batteries could fail and how much I hated spending on replacements. So, I did a bit more research, bought the highest capacity EBL AA/AAA 10 packs off Amazon that I could find hoping they'll hold up as well as the Fakespot filtered reviews seem to claim, and we're phasing out alkaline battery usage everywhere possible as the opportunities arise. It's wasteful and there's no point in replacing already still usable alkaline and heavy duty batteries currently in place, but once they die, off to the recycler and on to the rechargeable. This move should result in less damaged electronics, less toxic waste, and a small reduction longer term in overall household operations costs.

Edit: My household is going NiMH given we have very few voltage sensitive devices (mostly LED lighting and remotes), but if we run into anything needing a more hard-line voltage output (possibly any of my Klein tools, dunno yet), I'll be getting some Li-ions specifically for that purpose... so no excuses. There's a rechargeable for nearly any 1.5V alkaline AAA/AA/C/D battery operated device now!

This isn't about numbers and ROI with the investment, this is about simply reducing waste in as meaningful way as possible. Say what you will about the reductions in our pollution being a near meaningless drop in the bucket compared to the large corporations, but good stewardship is good stewardship. If you're going to use something of modern convenience (tool or otherwise), wisdom might dictate that you try and use it in as responsible of a way as possible.

So, who will join me?

[bill1827]

I watched that video and it's initially convincing. Unfortunately he glosses over a major issue, which is that NimH cells are 1.2V rather than the 1.5V of alkaline cells. For some usage that doesn't matter, but a lot of devices are voltage sensitive and NiMH cells won't work satisfactorily. I'd love to be able to change the 34 AA cells in the central heating controls, but it's not going to work.

[Daley]

@bill1827 I've thought about this, and you're not wrong, but most modern electronics taking batteries have to be more voltage tolerant than you realize (after all, the voltage curve on an alkaline goes from 1.5V down to 1.2V before dying). Biggest concerns are motors, audio broadcast equipment, and the like, and I don't doubt that you have power sensitive equipment.

This said, there are hard-line 1.5V out Li-ion rechargeable batteries in AA and AAA form factor and 9V now as well (this, too, was news to me as I'm used to only seeing 3.7V), for more voltage delicate applications. Under most conditions, the lithium rechargeables apparently can last about as long as cheaper alkalines can under high draw... the biggest difference is the power drop-off as they don't go weak before losing power, they just go dead - 1.5V out or nothing. They're considerably more expensive than even the NiMH cells, but might be worth it to make the switch all the same. EBL currently has 4 packs of AA 1.5V/2000mAh Li-ion batteries for $22.50, and an 8 pack of AAA 1.5V/800mAh batteries with 8 slot charger for $41, and some of their 9V 600mAh Li-ion batteries have a micro-USB port built in for charging, negating the need for a dedicated 9V Li-ion charger. The capacity isn't quite as good as the NiMH currently, but they can do a steady 1.5V.

I'm not a huge fan of lithium due to the environmental impact, but if you're okay with it in your cell phone, your laptop, your car, and you're mindful of the disposal and recycling? Adoption of these sorts of batteries should help drive cost down for more folks and perhaps increase storage capacity along with other Li-ion advancements. Something, something, don't let perfect be the enemy of good.

I won't argue that there aren't edge cases where alkaline batteries aren't still the preferred to superior choice, and even less potentially toxic than single use "disposable" lithium batteries. But I do think this is a very doable challenge for a lot of people now, especially in this community.

[RWD]

I've been thinking about this as well. We just used up a giant pack of alkaline batteries that we had bought years ago ("install by 2023") and I'm also sick of them leaking. We don't use a ton of AA batteries anymore so I just bought a 4-pack of Eneloops (we already had 4 though I haven't tested if they all still work) which should be sufficient for the near future.

[bill1827]

@bill1827 I've thought about this, and you're not wrong, but most modern electronics taking batteries have to be more voltage tolerant than you realize (after all, the voltage curve on an alkaline goes from 1.5V down to 1.2V before dying).

It's not really a question of "will they work" it's "how long will they work for". I've tried using NiMH AA cells in the past for low power devices (like these modern thermostats) and although they work initially they stop working in a very short time even though the cells have theoretical capacity left, typically a few weeks, whereas alkaline cells will run for 6 months to a year or more before replacement is needed. Even modern circuits aren't going to like the supply voltage dropping from 3.2V to 2.4V much.

[Daley]

@bill1827 I've thought about this, and you're not wrong, but most modern electronics taking batteries have to be more voltage tolerant than you realize (after all, the voltage curve on an alkaline goes from 1.5V down to 1.2V before dying).

It's not really a question of "will they work" it's "how long will they work for". I've tried using NiMH AA cells in the past for low power devices (like these modern thermostats) and although they work initially they stop working in a very short time even though the cells have theoretical capacity left, typically a few weeks, whereas alkaline cells will run for 6 months to a year or more before replacement is needed. Even modern circuits aren't going to like the supply voltage dropping from 3.2V to 2.4V much.

@bill1827 Did you even read past the first sentence you quoted from me here? You're so fixated on the NiMH voltage problem that you've completely missed the part where I mention there's also 1.5VDC Li-ion rechargables now as well, which completely negates your argument in this sort of situation. Within the past two years, multiple rechargable battery manufacturers finally figured out how to take 3.7V Li-ion batteries and the circuitry to charge and limit the output to 1.5V and stuff them all into the AA and AAA battery form factor while maximizing the storage capacity. Tenavolts was first on the market followed by Kentli, but EBL and a mess of disposable Chinesium brand names over on Amazon have the things now. The Li-ion cells are actually capable of being used with the very sorts of power sensitive devices that the NiMH cells can't.

Review & Teardown: Tenavolts AA Size 1.5V Li-ion battery (Youtube/Reddit)
Tenavolt Li-ion AA/AAA batteries
Kentli Li-ion AA/AAA batteries
EBL Li-ion AA/AAA batteries

They're expensive, but given the rechargable duty cycle of over 1000 recharges, one could even argue an ROI in this situation. There are EBL Li-ion 3000mWh 1.5V AAs where you can get an 8 pack and charger for $45, or $5.63 a battery. Even going for the rock bottom "premium" alkaline price of Costco/Kirkland AAs at $0.29/pop? You're claiming 6 to 12 months on replacement. These Li-ions will pay for themselves in less than 20 swaps. 10-20 years, though probably closer to 10 given how crappy alkalines are getting these days. The nicest part about tiny Li-ion cells? They don't really suffer the swelling problems of the larger cells.

At that price, isn't it worth at least trying in one or two of your somewhere between 8 to 34 HVAC controllers just to see what happens?

[Sanitary Stache]

The other posters here seem to have some critical uses for batteries. 

I got some lithium ion smoke detectors, I can't recharge them and they don't fit into my linked smoke alarm system.  I considered this to be the less safe/lazy option rather than constantly replacing the 9V batteries in the old smoke detectors.

I use the NiMH batteries for the kids toys, my wireless mouse and keyboard and my xbox controller.  All these because I hated having to buy new batteries and love being able to recharge the ones I have.  I guess I don't hate buying new batteries, it is really that I hate having bags of old batteries that I never find the motivation to dispose of properly, and then I have bags of leaky old batteries.

I am charging some AAA NiMH for my headlamp, which I doubt will work for very long in the cold, but they will work longer than the dead batteries I used to have.

[bill1827]

@bill1827 I've thought about this, and you're not wrong, but most modern electronics taking batteries have to be more voltage tolerant than you realize (after all, the voltage curve on an alkaline goes from 1.5V down to 1.2V before dying).

It's not really a question of "will they work" it's "how long will they work for". I've tried using NiMH AA cells in the past for low power devices (like these modern thermostats) and although they work initially they stop working in a very short time even though the cells have theoretical capacity left, typically a few weeks, whereas alkaline cells will run for 6 months to a year or more before replacement is needed. Even modern circuits aren't going to like the supply voltage dropping from 3.2V to 2.4V much.

@bill1827 Did you even read past the first sentence you quoted from me here? You're so fixated on the NiMH voltage problem that you've completely missed the part where I mention there's also 1.5VDC Li-ion rechargables now as well, which completely negates your argument in this sort of situation. Within the past two years, multiple rechargable battery manufacturers finally figured out how to take 3.7V Li-ion batteries and the circuitry to charge and limit the output to 1.5V and stuff them all into the AA and AAA battery form factor while maximizing the storage capacity. Tenavolts was first on the market followed by Kentli, but EBL and a mess of disposable Chinesium brand names over on Amazon have the things now. The Li-ion cells are actually capable of being used with the very sorts of power sensitive devices that the NiMH cells can't.

Review & Teardown: Tenavolts AA Size 1.5V Li-ion battery (Youtube/Reddit)
Tenavolt Li-ion AA/AAA batteries
Kentli Li-ion AA/AAA batteries
EBL Li-ion AA/AAA batteries

They're expensive, but given the rechargable duty cycle of over 1000 recharges, one could even argue an ROI in this situation. There are EBL Li-ion 3000mWh 1.5V AAs where you can get an 8 pack and charger for $45, or $5.63 a battery. Even going for the rock bottom "premium" alkaline price of Costco/Kirkland AAs at $0.29/pop? You're claiming 6 to 12 months on replacement. These Li-ions will pay for themselves in less than 20 swaps. 10-20 years, though probably closer to 10 given how crappy alkalines are getting these days. The nicest part about tiny Li-ion cells? They don't really suffer the swelling problems of the larger cells.

At that price, isn't it worth at least trying in one or two of your somewhere between 8 to 34 HVAC controllers just to see what happens?

Sorry, I've only just seen this.

You've answered your own question. Big Clive was discussing low self discharge NiMH cells as an economical replacement for alkaline cells. Rechargeable AA lithium cells (which I admit that I didn't know about) aren't economic. A bit of research show that they are about 20 times the price of adequate alkaline cells, so they would have to last for 10-20 years to break even in my application. That's probably longer than the lifetime of the devices they would be used in. Lithium cells  have other potential issues. If they are over charged or over discharged their life expectancy is drastically reduced. The charger may have over charge limits, but my devices will definitely not have over discharge limiting. (It's conceivable that these are built into the cells, but unlikely.) The flat voltage curve means that the battery SOC reporting in my devices will not work so you get no warning of a discharged battery; it just stops working which may not be noticed for some time.

I've tried replacing alkaline cells with NiCds, NimH, low discharge NimH in the past. None of them have worked well and none of them have been cost effective. I don't see that being any different with Lithium rechargeables.

[Abe]

We've been using rechargeable NimH batteries for some time now and have had no issues. Mostly for my kid's toys. They seem to work fine.

I don't have anything important that's battery-powered. Smoke detectors have a battery backup but are hard-wired also. Really nothing else important in the house that's battery-dependent except our computers and phones.

[AccidentialMustache]

Interesting. I'd seen the li-ion aa advertised to me when I picked up replacement sets for our older nimhs recently, but I had recognized none of the brands -- we have ebl chargers and I think had some of their nimhs before. Also, I like seeing the li-ion use a charger, not a usb plug. Those struck me as more thought in design than the "mini usb" ones from the no-names.

We mostly use nimh, but there are some devices where nimh just won't do. Oculus quest/wii controllers being one of them that comes to mind.