Rechargeable Alkalines?

[Connecteur]

When I was a child, I discovered that regular store-bought alkaline batteries could be recharged, and reused multiple times. I recall having a laptop back in the 90s which had a rechargeable battery pack that was alkaline not lithium. It lasted well over 10 years, much longer than any lithium battery pack.

Then, I guess it was in the 80s, I saw a TV commercial for an alkaline battery recharger. The inventor said he was a college professor who had invented a charger, so you could "save a lot of money by not buying new batteries all the time." Well, a few months later, I don't recall, but I think it was less than a year, when another company took it's place. I think it was called, "Pure Energy." The rechargeable alkaline batteries now cost several times as much as the regular store-bought kind, and the chemistry had changed in the store-bought kind, making them no longer rechargeable.

I'm going to sound a bit paranoid here, but it looks like industry conspired to get rid of a potentially positive contribution to the public good, which was sacrificed in the name of greed and profit.

[mikerj]

You can recharge alkaline cells to some extent, with some caveats.  You can not let them discharge fully, the smaller the discharge before charging the better. You can only charge them at a low rate and the capacity drops pretty quickly with repeated charging cycles.  Also there is the ever present risk of leakage.

[Connecteur]

You can recharge alkaline cells to some extent, with some caveats.  You can not let them discharge fully, the smaller the discharge before charging the better. You can only charge them at a low rate and the capacity drops pretty quickly with repeated charging cycles.  Also there is the ever present risk of leakage.

Yeah, no, I found it a waste of time doing that.

[tom66]

I don't think laptops ever used rechargeable alkalines.

Where they did exist they were a fairly novelty product. I think the one that I remember using was only rated to around 10 recharge cycles.  The novelty was they weren't much more expensive than a conventional alkaline and they had 1.5V output.

Most likely you had an early laptop with a NiMH battery, those definitely existed (and some even had lead acid batteries, like the Apple PowerBook 100).

[ejeffrey]

You could always recharge alkalines to some extent with the right charger, but only a few times.  And the risk of leaks was a real problem.

Purpose made rechargable alkalines were designed to recharge more, often claimed up to low 100s of cycles. They had a nice niche for a few years in the 90s and early 2000s before low self discharge NiMH batteries became widely available and inexpensive.  But they were only usable in low drain or occasional use applications because of their low cycle life.

[mikerj]

You can recharge alkaline cells to some extent, with some caveats.  You can not let them discharge fully, the smaller the discharge before charging the better. You can only charge them at a low rate and the capacity drops pretty quickly with repeated charging cycles.  Also there is the ever present risk of leakage.

Yeah, no, I found it a waste of time doing that.

Whether it's possible to recharge them is not open to question, you absolutely can and I used to do it pretty regularly as a young, penniless teen.  Whether it is worth doing given the limitations and risks is another question.

[amyk]

https://en.wikipedia.org/wiki/Rechargeable_alkaline_battery

25 full cycles, no wonder they fell out of popularity.

[Siwastaja]

I recall having a laptop back in the 90s which had a rechargeable battery pack that was alkaline not lithium. It lasted well over 10 years, much longer than any lithium battery pack.

You just remember wrong, probably both the battery type and how long it truly lasted.

[Kleinstein]

The recharging of alklines was only a few cycles and the recharge was only to a fraction (like 50%) of the capacity. On the positive side the batteries where not really more expensive than regular alkaline.  The big issue was more the risk of leakage than a limited number of cycles.

Voltage wise they should be the same as regular alkaline: some 1.6 V when full and going down over time to maybe 1.2 V usable. When the 1.25 V from NiMH or NiCd were not enough, the useful capacity of the alkaline cells also goes down.

[jogri]

I'm going to sound a bit paranoid here, but it looks like industry conspired to get rid of a potentially positive contribution to the public good, which was sacrificed in the name of greed and profit.

No, it's just a truly horrendous system without many benefits but with a bunch of problems.

-Your electrolyte (water) breaks down and releases hydrogen while charging -> that has to vent, and less electrolyte automatically means lower performance
-The mangan oxide on the cathode side is VERY prone to irreversible side reactions -> massive decrease in capacity per cycle
-The zinc anode is the worst offender of them all, it will never grow into a useful rod again and instead form dendrites everywhere -> lowers capacity, if you're lucky it just short-circuits the battery during charging

Better to just drop it entirely and avoid having to sort out yet another type of batteries for recycling.

For reference, metallic Lithium anodes have the exact same dendrite problem. Even today, this is not solved at all, which is why every commercial Li battery uses Lithium in graphite instead. We would very much like to use Li metal, but it just kills the battery after a few cycles.

And the main reason for Li was energy density, you'll never get close to that with a chemistry that relies on heavy atoms (Manganese, Zinc) in your cell.

[Connecteur]

I'm always a bit mystified by the way some people step up to defend planned obsolescence.

[Siwastaja]

I'm always a bit mystified by the way some people step up to defend planned obsolescence.

I'm more mystified how some people see malice where there clearly is none. Planned obsolescence is pretty much real but mostly dealt on software side today. But battery technology has improved so much in all respects that you need to be pretty delusional to think it was somehow better in the past.

I had a NiMH laptop in 1990's, too. Battery last 60 minutes of actual use and after 2 years of use it was dead. Good riddance.

[jogri]

Me? In my dayjob i'm a chemist doing research into the behaviour of Li metal anodes...

It has nothing to do with planned obsolescence or sinistre cabals, we just don't know how to do it, even 30 years later in research (for reference, the current Li batteries were developed in labs in the 80s).

Back then, everything better than a lead acid was a success, but that wasn't a particularly high bar so of course some weird "yeah, it somewhat works for five cycles with horrendous efficiency" was okay, but with NiMH there just wasn't a reason to continue.

The beauty of alkaline batteries is that they are dirt-cheap to manufacture, re-engineering them into something better suited for recharging probably would've taken a ton of time (we don't even have a solution for the major dendrite problem 20+ years later) and driven up the price, for a chemistry where it was plain obvious that it would still suck. Just not worth it.

[tooki]

I'm always a bit mystified by the way some people step up to defend planned obsolescence.

Maybe because:
a) Not everything that involves a product's life is planned obsolescence.
b) Those people actually know what they're talking about, as opposed to your constant approach of knowing very little (often entirely wrong) and somehow thinking that is equivalent (or even superior!) to someone else's actual expertise.

[tom66]

I'm always a bit mystified by the way some people step up to defend planned obsolescence.

Maybe because:
a) Not everything that involves a product's life is planned obsolescence.
b) Those people actually know what they're talking about, as opposed to your constant approach of knowing very little (often entirely wrong) and somehow thinking that is equivalent (or even superior!) to someone else's actual expertise.

Indeed. There are clearly some examples of planned obsolescence.  But in many cases, people blame planned obsolescence when there is a better explanation, which is that cheap things only last a short amount of time.  ("Buy cheap, buy twice")

Most brands** do not get repeat customers if they produce crap.  So there is really no economic incentive to making a product deliberately fail, because they will not make additional sales from that customer.  Put it this way, if someone goes and buys a Samsung TV that dies on them out of warranty, are they then going to buy a Samsung fridge or dishwasher?  Probably not, as their image of the brand will be tarnished.  And, they are also unlikely to buy another Samsung TV.   So where is the incentive for Samsung to build a product that fails quickly?  There isn't one.  However, there is a big incentive to get the sale price of that TV down below $499 so they can ship as many as they can.

**There are some obvious exceptions, I think Apple is the biggest one, where people like to 'upgrade' every year or two for whatever reason.  But even then I think there is not so much a built in obsolescence, as an unwillingness to provide endless support for a once-sold product.  iPhones get software updates for 7 years, but the phones aren't useless after that date.  It just becomes a money sink for the company to continue providing updates, since the updates would need to be progressively stripped down to maintain compatibility with older architectures and processors, and some devices simply won't keep up with the software changes.

[BradC]

When I was a child, I discovered that regular store-bought alkaline batteries could be recharged, and reused multiple times.

I did too. I recall breadboarding a pulse charger for them when I was back at school. This worked brilliantly for things like my walkman until the day one "went off" in the charger and sprayed electrolyte all over my desk and carpet. About 5 cycles seemed to be the limit (from distant memory) until the sealing surfaces were compromised to the point they let go.

[Siwastaja]

I did too. I recall breadboarding a pulse charger for them when I was back at school. This worked brilliantly for things like my walkman until the day one "went off" in the charger and sprayed electrolyte all over my desk and carpet. About 5 cycles seemed to be the limit (from distant memory) until the sealing surfaces were compromised to the point they let go.

Yeah. In one case I can still recommend recharging alkaline batteries today: it's the case you run out batteries, don't have replacements, and stores are not open to go buy replacements. Then just take the dead cells, and slowly (like at C/10) charge them from a lab supply for a few hours. Maybe you are able to recover 30-40% of charge quite safely, enough for the batteries to work again until you can go and buy replacements. I have successfully done exactly this a few times.

[Zero999]

This appears to be another troll thread.

I've tried it before and it was never good enough to be worth it. I recall seeing a special alkaline charger in a mail order catalogue back in the 90s. It was a stupidly expensive price and probably consisted of a transformer, bridge rectifier and resistor, like trickle charge NiCad chargers did back then.

[tggzzz]

When I was a child, I discovered that regular store-bought alkaline batteries could be recharged, and reused multiple times. I recall having a laptop back in the 90s which had a rechargeable battery pack that was alkaline not lithium. It lasted well over 10 years, much longer than any lithium battery pack.
...
I'm going to sound a bit paranoid here, but it looks like industry conspired to get rid of a potentially positive contribution to the public good, which was sacrificed in the name of greed and profit.

Those batteries would have been NiCd or NiMH.

Yes, you are sounding as if you latch onto unlikely conspiracy theory ideas. If you want to avoid that happening, I suggest you do something conspiracy theorists conspicuously avoid: decent recearch + Occam's Razor.

[tggzzz]

I'm always a bit mystified by the way some people step up to defend planned obsolescence.

That is something a troll would say.

[bdunham7]

I'm always a bit mystified by the way some people step up to defend planned obsolescence.

There are not a lot of defenders of planned obsolescence here!  Lithium batteries and charging techiques have gotten vastly better and laptop batteries can and do last 10 years.  My phone battery is 7 years old IIRC and hasn't degraded noticeably.  I use rechargeable 9V/AA/AAA batteries in almost everything now (Li-ion for 9V, NiMH Eneloop for AA/AAA).  I even have Tenergy C and D cells for flashlights.  Rechargeable alkalines were an idea that just didn't work out due to competition with better products.  I'm just imagining life if my smoke detectors used rechargeable 9V alkalines.

An uncited passage from the Wikipedia page:

If they are discharged by less than 25%, they can be recharged for hundreds of cycles to about 1.42 V. If they are discharged by less than 50%, they can be almost fully recharged for a few dozen cycles, to about 1.32 V. After a deep discharge, they can be brought to their original high-capacity charge only after a few charge-discharge cycles.

That doesn't sound particularly useful and certainly not better in any way than NiMH.

[Connecteur]

When I was a child, I discovered that regular store-bought alkaline batteries could be recharged, and reused multiple times. I recall having a laptop back in the 90s which had a rechargeable battery pack that was alkaline not lithium. It lasted well over 10 years, much longer than any lithium battery pack.
...
I'm going to sound a bit paranoid here, but it looks like industry conspired to get rid of a potentially positive contribution to the public good, which was sacrificed in the name of greed and profit.

Those batteries would have been NiCd or NiMH.

Yes, you are sounding as if you latch onto unlikely conspiracy theory ideas. If you want to avoid that happening, I suggest you do something conspiracy theorists conspicuously avoid: decent recearch + Occam's Razor.

I may have been a child, but I certainly knew what types of batteries I had.

[bdunham7]

I may have been a child, but I certainly knew what types of batteries I had.

The individual cells, sure.  The laptop battery pack, I'm not so sure.  That sounds improbable, but if you could cite the specific model that might help.

[coppice]

When I was a child, I discovered that regular store-bought alkaline batteries could be recharged, and reused multiple times. I recall having a laptop back in the 90s which had a rechargeable battery pack that was alkaline not lithium. It lasted well over 10 years, much longer than any lithium battery pack.
...
I'm going to sound a bit paranoid here, but it looks like industry conspired to get rid of a potentially positive contribution to the public good, which was sacrificed in the name of greed and profit.

Those batteries would have been NiCd or NiMH.

It depends what he is remembering. If laptop includes some of the very simple note taking machines, he might be remembering alkaline non-rechargeable cells. If he is remembering a more conventional type of laptop, that would have been NiMH from the early 90s, with some NiCd ones before that. Most of the early portable machines only operated from mains power.

[RoGeorge]

I've rechearged a couple of times some alkaline batteries.  Once did an experiment out of curiosity, with a handful of AA/AAA taken from an EE waste, various brands.  It mostly worked, but with various results.  Here's a chart while charging 2 different brands of AA under the same charging current (and these are two close results, other batteries were differ much wildly):


Chart from https://www.eevblog.com/forum/projects/why-the-beak-like-shaped-v-then-the-wiggling-while-recharging-alkaline-at-ict/

Once I've even did a fan-less constant current charger https://www.eevblog.com/forum/projects/recharge-non-rechargeable-alkaline-batteries-with-a-broken-leds-light-bulb/ so I could try more brands without the fan humm of my DP832 power supply.

My conclusion, most of the times it is possible to put some charge back into alkaline batteries, but:
- definitely not worth the effort
- some might not take charge at all
- what's worst, ABOUT HALF of the AA/AAA alkalines WILL VENT AND LEAK a few days after recharging! 

Not kidding, many of the AAA/AA I've fooled around with (about 20-30 pcs.) did vent somewhere in the first 2 weeks.  I'm talking about batteries that were recharged then left sitting on the workbench, indoors, no temperature stress, no load.  They vent and leak out of the blue.  A few of them happened to vent and leak while I was at the PC, so I could hear them:  a soft pop, short hiss, followed by small visible bubbling/leak of the corroding thing at the negative end.