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    I’m curious why low current devices like those mentioned in the article themselves don’t incorporate a boost circuit to prolong battery life, then? It sounds like the circuit is cheap, can be miniaturized - perhaps incorporated into a standard vreg chip.

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      Margins are low on many of these devices and even a few extra components adds small amounts of size, weight, cost and complexity. In the end there’s not much incentive for designers working against a deadline to add more cost and things to go wrong.

      Having said that, in cases where battery life is really critical designers will often use a regulated boost converter as their power supply and that does essentially the same thing.

      Also note that the title is misleading - in most cases you might get a few percent extra battery life. 800% improvement would definitely be an unusual case.

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        It’s called business.

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        Something not called out in the article, does the current decrease over time? If so, is this bad for devices?

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          Whelp, I asked my dad (long time embedded engineer) the same question and he had a pretty good answer

          This is an interesting idea. The discussion seems to be all about open circuit voltage (vs under load). If the booster can maintain 1.5 volts at whatever current the device load is, then the device won’t care. So no harm done to the device.

          But as the cell’s voltage drops, the boost circuit is going to require more and more current from the cell, to source constant power to the device.

          I think the explanation presented implicitly assumes a simple resistor across a battery, where as voltage drops, the current also drops (V = IR). But the active boost circuit is going to require more* current from the battery as voltage drops, not less. And that is where I think the rosy projections of 8X fail.

          I do agree that this should suck more energy from the battery. But my hunch is more like 2X, not 8X.

          There are probably some electrochemistry valance electron angles, too.

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            I sometimes do electronic design for money. I totally agree with your dad. The 8X claim would only be plausible for very bad quality batteries and very very low power devices. In most cases you’d be lucky to get more than a few percent improvement out of this.

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              The maths in the article is … unconvincing.

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              Maybe it’s just the Joule thief circuit in pretty packaging? Why don’t devices like TV remote controls have these built-in?

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            Cool idea, but I wonder what the idle drain of the circuit is. I mainly use alkaline batteries for long-lasting idle stuff (remote controls). If this converter is sitting there sipping current trying to maintain 1.5v over years, it may be more detrimental than helpful.