The Batteriser Explained | Hacker News Reader

The Batteriser Explained

eevblog.com

168 pointsMrBuddyCasino59 comments

Saying “1.5V of Energy” is incredibly embarrassing for a company that is trying to market a product like this. Perhaps they are just trying to dumb it down for the masses?

I think they're being intentionally misleading - and counting on the "dumb masses" to not understand that - so they can claim that 8x improvement, since it comes entirely from the also-misleading "more than eight 0.1 volt steps between 0.6 and 1.5 volts" statement. (It's technically true, but irrelevant.)

As an aside, do schools today teach power, energy, voltage, and current in the standard curriculum? I know I was taught that (and Ohm's law) somewhere between elementary and middle school, but that was many decades ago...

Also those discharge curves are constant-current, but devices which already have boost converters in them will be drawing constant power, i.e. as the voltage goes down the current will go up. That means the discharge curve will look even steeper at the end, with less "wasted" energy.

At least they didn't claim "up to 8 times or more".

I was taught basic electronic concepts in 11th grade introductory physics (back in the mid-90s). I suspect things are a little different and more parallelized these days. Science course progression in my school district was as follows:

7th grade: "life" science (intro to biology concepts)

8th grade: earth science

9th grade: biology

10th grade: intro chemistry

11th grade: intro physics

12th grade: AP physics / biology / chemistry

>At least they didn't claim "up to 8 times or more".

At least they didn't lie even more

> As an aside, do schools today teach power, energy, voltage, and current in the standard curriculum? I know I was taught that (and Ohm's law) somewhere between elementary and middle school, but that was many decades ago...

I got it in my second level of engineering physics in college. Before that I had learned some of it independently for my senior project.

This was in the early 2000s.

I guess the answer is "depends on the curriculum".

As much as I like Dave Jones, I think he's concentrating on the wrong bits here.

The idea is completely bad. Sorry. It's a pile of crap. It shouldn't be on the market.

Sure you can build a boost converter that gives you a constant 1.5v. That's not a bad idea. I've actually designed a couple of these myself on a larger scale over the years (professionally, for military radio equipment, not Joule Thief hacks). That's not under debate. The following points are:

1. Even the best alkaline batteries leak if you discharge them too much so you'll end up destroying your equipment and the Batterisers that you invested in at the same time. Seriously, take a 220 ohm resistor and stick it across a Duracell AA battery and leave it for a few days. You will come back to a rancid mess.

2. There is a cost. So you're going to need 4 of these for your average device that requires a 6v supply. now my 12v radio packs are 8xAA batteries so imagine the incidental cost over the top of the batteries there. To power kids toys you could have tens of these in the house. Over the top of disposable batteries, it's a poor investment.

3. 8x is simply horse shit, as DLJ points out. Even with a fairly efficient conversion ratio, and I haven't done the figures, just a finger in the air estimate based on the amount of energy your average alkaline AA has, you're looking at 1.2-2.0x the life.

4. Wonderful things like AA batteries are terribly variable in the tail end of their discharge curve. Not all batteries in a pack are going to still be kicking out current or even have a suitably low internal resistance compared to their immediate colleagues. If one of these fails early, it will take the advantage away from the rest of the cells instantly.

5. Noise. Boost converters usually generate a lot of electrical noise in the signal paths. If you have any analogue parts, particularly audio that are expecting to have a relatively noiseless power supply (batteries are quite noise free) then the design will perform worse with these.

Now the killers:

1. If this was such a great idea, why is it not built into the equipment? (because it represents a risk to the equipment)

2. Why the hell would you bother with this when Sanyo (well Panasonic now) Eneloops represent a better investment than both alkaline batteries and these. They handle over 1000 charge, discharge cycles no problems at all, have a good very good shelf life due to low self-discharge characteristics, don't leak and have a decent peak current capacity and discharge curve.

It's just a waste of time.

Good post.

But why 1000 charges is useful for most home equipment where batteries last a relatively long time ?

Only because they are then fungible. Once you dispose of that calculator that takes 4xAA batteries and lasts 6 months, you can whack the cells in a Furby's butt and charge them up once a week until your children get rid of the damn things :-)

You, sir, are quite clearly not the parent of a pre-teen child

We go through packs of AAs like popcorn around here

Two words: Wii Remote.

> 1. If this was such a great idea, why is it not built into the equipment? (because it represents a risk to the equipment)

Because pennies add up when making millions of units, and the TCO including batteries isn't a point of competition. Still, it would obviously be more efficient to run a larger boost converter on 4 cells in series rather than multiple tiny energy-harvesting ones.

I've also got to wonder about the standby power of this device. IR remotes are on very little and last for years with the right battery, so any additional draw is going to greatly reduce their lives. And like you said, high draw devices are changed regularly so recharageables make more sense.

IMHO products like this aren't really about the tech and appeal to a large audience for their simplicity, not their efficacy.

Thanks for sharing. I was wondering, why do we need the sleeve ? Can the voltage boosting module be part of the remote itself ? Isn't that what a dc-dc module does ?

This question and more on the previous discussion: https://news.ycombinator.com/item?id=9644931

The sleeve is to get access to the other terminal, the booster circuit needs to see both terminals to work.

I understand what you mean. But in my remote, the batteries are not arranged in serial; they are arranged in parallel. That being the case, my remote can see both terminals of a given battery. Hence, I fail to see, as to why the mechanism cannot be implemented as part of such devices..

The same applies to my wall-clock (which uses a single battery)

They can be. And in fact, in plenty of electronic devices they are since operating from a variable supply voltage is not an option so the typical battery powered device uses dc-dc converter like the one in the article only it does not operate on a single cell but on all cells in series. And that works just fine.

> But in my remote, the batteries are not arranged in serial; they are arranged in parallel

Are you sure? That's pretty uncommon. Are the poles oriented in the same direction or opposite ones? Is one set of poles connected to a pair of terminals shared by a single conductor and the other set using two distinct terminals?

It looks just like this :) http://s289.photobucket.com/user/stranger205/media/battery_s...

Yeah, that's in series.

In case the remainder of the electronics can not work with the low voltage directly, often a boost converter is integrated in the device. Remotes mostly don't: their electronics can run at very low voltage, at the end of the battery life, the range is reduced because the ir led produces less light.

There's no reasons you can't put a voltage boost circuit into a device other than it would be cheaper not to and consumers will blame the batteries, not your device, if you don't. (also, if your device functions fine with low voltage batteries there is no need to.)

> if your device functions fine with low voltage batteries

Probably not a good idea. Really spent batteries tend to leak and damage the device.

Not working makes the owner change the batteries.

Even with a boost converter, it'll still stop working

>There's no reasons you can't put a voltage boost circuit into a device

It will kill rechargeable lithium batteries.

A single cell AA lithium likely already has a 3.7v (IIRC) to 1.5v step down, but also likely has a cut-off voltage to protect the internal cell too.

If it's built-in lithium then you're as likely put in a step-down or a buck-boost to regulate raw lithium cell pack voltages to whatever the device needs internally, but that also needs a self-protection cutoff.

There's also an efficiency loss from the extra circuitry, particularly when the batteries are good enough that there's no benefit yet.

They could add a bypass circuit around their boost converter, which would give virtually 100%[1] efficiency until the booster actually fires up.

Something like the TI TPS61291[1] draws only 15nA in bypass operation, and maybe 85% efficient in boost.

[1] The bypass switch itself will have some resistance, the part below is ~1.2ohm, which might be significant depending on your load.

[2] http://www.ti.com/lit/ds/slvsbx9a/slvsbx9a.pdf

Why not put it in the battery?

Isn't this just a DC-DC converter? How can they have a patent for something that was invented decades ago? I used to read a lot of IC datasheets in my previous job and such battery extenders are given as reference designs in the datasheets.

Their patent is on the mechanical design, not the electrical design.

Dave Jones can be a little dramatic during videos like this. I wish he spent more time talking about ways you could actually achieve the claims of the product and less time just cutting down the designers. It's easy to point out all the things you see wrong with something, but it's much harder to try to answer the question, "how could we make it work anyway?".

And his T-shirt says "I only give negative feedback" with a circuit diagram of that type :)

Maybe the issue is drawing the line at "we can make it work, but at such cost & effort as not be worthwhile" in a way that makes drawing the line itself worth the time & effort in doing so. Squeezing the last bit of energy out of an alkaline battery ultimately costs more than that energy is worth, as is trying to explain to the gullible/uninterested why that is so.

> talking about ways you could actually achieve the claims of the product

The thing is, you fundamentally cannot achieve the claims of the product, or rather: you can only fulfill the claim for an area of application which consists of badly designed circuits to begin with.

Would you (rightly...) call bullshit on me if I claim that I developed a patch to gcc that makes all software 800% faster? You probably would start explaining to me that typical software is limited by memory bandwidth, or might wait for disk I/O... and that one might achieve 800% speedup only at some hot-spots in exceptionally rare cases of particularly badly coded programs.

You can't achieve the claims of the product.

If one explained why the “lose 15kg in 10 days” ads are bogus, would you ask of him about ways to actually lose 15kg in 10 days?

"how could we make it work anyway?".

In this case, you can't. At least, not for practical application.

One's inability to solve a problem does not invalidate their ability to identify it.

> ways you could actually achieve the claims of the product and less time just cutting down the designers

Why wouldn't the responsibility of "achieving the claims of the product" fall on anyone other than the designers of said product ?

I think he's doing his job and very fairly and objectively at that.

What I wanted to read about but couldn't find it was the actual ROI of this product. How many batteries must I use so that it would make financial sense to buy the product? (So that we could compare with actual results and see if they match)

The makers haven't given enough information for anyone to calculate this.

A similar (although as the article says, not identical) way to get more life out of a battery https://en.wikipedia.org/wiki/Joule_thief

The guy who invented the term "Joule thief" incidentally also has lots of videos on LED lighting and other miscellaneous stuff:

https://www.youtube.com/user/bigclivedotcom

Hey, I've been watching that guy on youtube recently, I didn't realise that he was the guy behind the Joule thief!

What I don't get: I stopped using alkalines long ago, and have since settled for Eneloop rechargeable batteries. They can be reasonably used even in wall clocks, due to their low rate of self-discharge.

Why do people still buy the regular ones?

They're cheap, usually last longer than rechargeables (I think) and recharging is a pain?

Not very environmentally friendly I know.

Most things seem to have built-in batteries these days so there are fewer and fewer reasons to use any of them I guess.

Higher up front costs. A 4 pack of double or triple As only costs a few bucks, less than a dollar per cell even at retail prices. Comparatively you need to spend at least $10 just to get a couple eneloop cells, 2 to 3 dollars per cell, plus at least that much for a charger (a decent one is more like $40).

Then you have the hassle of keeping things charged, which realistically means having a stock of extra batteries lying around. Also, it doesn't help that the cheapest rechargeable batteries and chargers lead to a comparatively bad user experience (batteries not holding a charge long, low lifetimes).

Similarly, look at kitchen knives. Most folks have sub-par stamped kitchen knives instead of a decent chef's knife even though you can get decent ones for 30 to 40 bucks or so. It's a matter of high up front costs and not knowing what they're missing.

True, I always have charged spares and a high quality charger. Still, in the long run its cheaper, and better for the environment.

But then I also own high-quality kitchen knives and sharpen them regularly, cutting tomatoes with a blunt knive is something I refuse to do. Guess you're right.

NiMH cells are expensive compared to alkaline cells. A quick check on Amazon shows that, when buying a decent amount of AA cells at a time, alkalines go for about $0.28 each compared to $1.67 each for NiMH cells.[0][1] Add in a charger (and consider that most cheaper chargers are really crappy--look for NLee the Engineer's reviews[2]) and many don't consider the benefits to outweigh the initial capital costs. (Also, alkalines tend to operate at 1.5 V for a good portion of the voltage curve whereas NiMH cells are usually around 1.3 V. This can cause problems in some devices, although less so today than, say, ten years ago.)

I absolutely agree that NiMH cells are superior in almost every way, but it's not irrational to prefer disposable batteries.

[0] http://www.amazon.com/AmazonBasics-Performance-Alkaline-Batt...

[1] http://www.amazon.com/AmazonBasics-AA-Rechargeable-Batteries...

[2] e.g. http://www.amazon.com/review/RMWO7UZ9TAVRF/ref=cm_cr_rdp_per...

Yep, voltage on the eneloops by comparison is 1.2V. Lots of battery operated toys work better with 1.5V batteries. There are rechargeable alkalines that provide 1.5V but they are very unreliable and the rest of the rechargeable AA market is lower voltage. So batteriser would be pretty neat if it works as advertised.

You really wouldn't want to use this approach with rechargeables, as they degrade pretty quickly if discharged too far (which is what this would do)

The things I still use batteries for last long enough to not really justify the extra cost of rechargables, which I have a history of losing. Remotes and clocks are pretty much the only things I need batteries for and they last a very long time on even the cheap dollar tree batteries.

Aren't your Eneloop's just trademarked top of the line NiMH cells? A quote from the article: "For starters, and this is important, any product that is designed to be used with both rechargeable NiMH and Alkaline primary batteries (a design goal of most good products), must work down to at least 1.1V per cell." IF you can find a device that won't run on a rechargeable (which may be hard to do), then you need an alkaline, thats just how it is.

The other argument is financial. I have a cheap wall clock that runs about a year on a AA. The prices are very hard to understand on Amazon but you're looking at about $4 or more per rechargeable eneloop AA and around 40 cents for an alkaline AA in bulk. I think its fair to compare onsie-twosie rechargeables to bulk disposables; isn't that the entire point of being rechargeable? So I need to keep that clock powered up for more than a decade to run a profit on the rechargeable. Honestly I don't think it'll hold up that long. You need to recharge that dude more than, say, every six months, to run a profit, longer than that and its cheaper to dispose.

Presumably they don't charge $4 for a top of the line NiMH and 40 cents for an alkaline just for fun, I think its extremely safe to estimate the rechargeable causes at least 10x the environmental damage as the alkaline. Obviously the linear damage is 10x alone, some employee somewhere will get that $4 instead of 40 cents and buy gasoline or food or other petrochemical related substance, plus the issues with nickel refining, the electrolyte is somewhat more exciting, etc. So its not just a financial win.

Voltage, mainly. Sometimes NiMH batteries just don't do the job for very long- it's like putting in an almost dead battery to start with. My kids' wii remotes, for example, don't work very well on rechargeables. They work for a little while, but I was constantly recharging them to the point where it got stupid.

My Wii remote worked fine on Eneloop batteries.

For regular alkaline batteries, Nintendo says 60 hours lifetime using just the accelerometer, and 25 hours using both accelerometer and pointer. That's not very long for a kid that's seriously into a game.

Is it possible that you are also going through non-rechargeable batteries reasonably fast, but don't notice because, say, the kids can change those without your involvement, but with rechargeable batteries you are the one who handled recharging so saw every battery swap?

Another thing to watch out for is that alkaline and NiMH have very different discharge curves. Alkaline starts at 1.5, then falls steeply to around 1.3-1.4, then drops at a more gentle rate down to around 1.1, and then plummets.

NiMH starts at around 1.3, drops to 1.2, and then stays close to level until near the end, then starts dropping faster for a bit, then goes over a cliff.

If a device was not designed specifically to allow for NiMH, it is going to assume a discharge curve that follows the alkaline profile. When it uses voltage to estimate how much battery life is left, it is going to get confused by the NiMH curve.

If you put fresh NiMH batteries in a device, use it a while, and check the battery level, it will be reported as much lower then it really is. This can fool people into replacing the batteries early, because they figure it is falling fast and they don't have much time left.

I had one device where it would report not long after I put fresh batteries in that it was down to 60%, and if alkaline had fallen to 60% that fast, it would be time to put new batteries on my shopping list...but in reality with the NiMH it would actually stay at about 60% for weeks.

What I'd really like to see is more consumer devices that run on removable lithium-ion cells. I have several flashlights and power banks[0] that run on 18650 cells. I'm thinking of adding a Solderdoodle soldering iron to that and maybe constructing a device to provide power to my laptop's DC port while changing its battery.

Of course, I don't have my hopes set too high for this, as there's a certain degree of liability risk in handing lithium-ion cells to consumers; they don't take as kindly to abuse as alkalines and have been known to explode on occasion when severely mistreated.

[0] I'd rate the Miller ML-102 power bank as a best-in-class product for running on removable 18650 cells and putting out 1.8A on a single cell. It costs $6.

8 x improvement on a dead battery... that's still a dead battery isn't it?

Yes, but it's eight times more dead.

The conclusion reached: hype can be very, very wrong, but nevertheless: it is hype. Making bold claims nevertheless gets you some eyeballs/ears far and wide ..

That's a supergood write-up.

In short: the tech probably works, the efficiencies claimed are likely bunk and there are some possible risks that need to be researched.

The tech probably kinda-works, was what I took away from that.

If you use it on a new battery you're likely to get worse life out of it, if you use it on a rechargeable it might damage it, but if you use it on a 'dead' alkaline you might get some more life out of them. How much will depend on the tolerances of the device you're using them in.

--edit-- oh, and it will do an end-run around any battery gauge your device has.

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