It's an old article, but still mostly correct. Several developments have changed the landscape over the past decade. The Chinese have pretty much taken over the battery manufacturing industry. As a result, the quality of many low-production battery series has gone down dramatically. Some cells that once had a 10-year shelf life will now be completely useless within two years.
A more positive development has been the improvement in power electronics. Quality consumer electronics will now often include power conditioning circuits so the "cut off" voltage from a battery is no longer relevant. The batteries can now continue to power the device until they are completely discharged.
(See: https://www.ti.com/tool/TPS61280EVM-585)
Great AA Alkaline Battery Test (2016)
141–150 of 195 posts
Re: Great AA Alkaline Battery Test (2016)
#142I think the main issue with AA Alkaline is the proliferation of cheap low-self-discharge NiMH cells (aka: Eneloop, but also Energizer and other brands have good LSD NiMH available). A huge number of appliances seem to be designed for the 1.35V NiMH chemistry now. Perhaps a random TV-remote still prefers Alkaline but most seem to work fine with NiMH. ----- Buying a pack of 20 NiMH cells and rotating your collection be…
Just want to signal-boost Markus Wandel's Ni-MH battery tester/matcher on Github: https://github.com/MarkusWandel/battery-tester
I'm (lackadaisically) building a version of it now, in order to get matched pairs and fours of the 40-plus eneloops that we have. And identify the bad ones, of course.
Re: Great AA Alkaline Battery Test (2016)
#143Earlier quoted context omitted.
I'd seen those in the past. Prices have come down. Am curious what are the benefits over NiMN.
should be little to no memory effect unlike NiMH
Modern, high-quality NiMH has little to no memory effect. Eneloops are the gold standard, though rumor has it many other brands have caught up.
Re: Great AA Alkaline Battery Test (2016)
#144Panasonic (who sell expensive alkaline cell) or FDK (who made eneloop) 's alkaline is my choice for expensive/important appliances.
Re: Great AA Alkaline Battery Test (2016)
#145I think the way we went to 1.2v for rechargables when we design to higher nominal voltage is really confusing. Why we didn't either shift the design basis to use 1.2-1.1 as a signal so we had better outcome when 1.2 drops off, or design the 1.2 cells to deliver 1.4 dropping to 1.2 and 1.1 is beyond me.
Because in practice, we're not designing for the consequences of 1.2 It shelves on 1.2 forever, tails, and then BOOM its gone. we should have designed for that curve, not for 1.5 -1.4 -1.3 -1.2 ....... BOOM
Re: Great AA Alkaline Battery Test (2016)
#146Earlier quoted context omitted.
Just to clarify your point there: Charging batteries as pairs is what kills the rechargeable batteries. There is no way for the charger to keep track of both batteries at the same time so it just charges until both should be done. If one of them is bad, the charger will kill the other one too. If they are differently charged, it will kill one of the batteries and next time it will kill the other battery. (Kill as in…
This is what killed me when I started swapping Alkalines for NiMH in the 00s. Every single charger sold in stores only charged in pairs, and because even then USB was creating a 5V world most things that needed batteries used 3 of them. Even the charger that Panasonic sold with the Eneloops requires matched pairs. The other issue being that NiMH seems to top out at AA size. Finding C or D sized rechargeables is basic…
There is a more expensive eneloop charger that does individual cells. I have been mixing cells for charging for years with no problems.
Re: Great AA Alkaline Battery Test (2016)
#147Let me leap in here to ding Duracell. They used to be my goto battery, but over the past few years (there was a hedge fund takeover, which IME rarely results in improvements to long-standing quality products) they've turned into liabilities - specifically, they are extremely prone to leaking once even a little bit discharged. To this day I open old kit and there can be duracells in there with "use by 2010" or even ea…
Same here, lots of leaks-- some family even has had a drawer full of unexpired Duracells leak. Myself, I've switched over completely to NiMh except when unsupported by the device to remove the change of leaks (Nest x Yale door lock in particular, which detected NiMh as low battery even when 90% of the cell capacity is remaining). AmazonBasics has been bad with leaks too. Edit: I have a Powerex MH-C980 and that has si…
I just replaced some ~2 year old 9v and AA from various detectors around my house, all rayovac and half were leaking and I had to use some sand paper to clean the terminals. Yeah I know you're supposed to replace once a year but it is what is. Seems from this thread people have seen leakage from many different brands from cheap ones to "duracell"
Re: Great AA Alkaline Battery Test (2016)
#148> This can be implemented basically with a fixed value of resistance, but because of the way resistance interacts with voltage, it’s actually very gentle on the battery. As the battery voltage falls, the current falls accordingly, so the delivered power falls even further. For modern appliances, this type of loading is not common. Dumb question - is it at all possible to design a modern device which operates this way…
Have you ever used an old flashlight in the 80s or 90s? As AA charge fell, the light got dimmer and dimmer. Today, we have devices that do the exact _OPPOSITE_, pulling the last bits of electricity out of the cells through boost-converters or whatnot (boost converters existed back then, but weren't as efficient or cheap as today). Consumers demanded consistent and reliable performance no matter if at full-battery cha…
Flashlight nerd here.
This behavior is still common in flashlights. Flashlights using three alkaline (or NiMH) batteries in series, or a single Li-ion cell can drive a white LED via a linear regulator (or occasionally just a transistor), and it will dim as the battery falls below the forward voltage of the LED at its maximum output. At higher price points, a single Li-ion cell and a regulated buck converter is common to see and much more efficient, but maximum brightness is still usually limited by battery voltage.
A flashlight using a single AA or AAA battery must use a boost converter because all white LEDs require about 3 volts. Even these often don't produce stable output as the battery drains, which is sometimes intentional because that behavior would produce terrible battery life with alkalines due to their high internal resistance. It's fine with NiMH.
Even Li-ion lights with boost converters don't always manage full output on a low battery because it's common to find overdriven components on a 20mm driver board (it needs to fit in a pocket) that's trying to push as much power as possible (lumens sell lights). Inability of the electronics to maintain full output isn't necessarily a significant limitation in the real world anyway; a 25x100mm aluminum tube pushing 40W gets hot fast, and there's almost always some sort of thermal-throttling mechanism. That said, full output on a low battery usually earns praise from reviewers.
Re: Great AA Alkaline Battery Test (2016)
#149Let me leap in here to ding Duracell. They used to be my goto battery, but over the past few years (there was a hedge fund takeover, which IME rarely results in improvements to long-standing quality products) they've turned into liabilities - specifically, they are extremely prone to leaking once even a little bit discharged. To this day I open old kit and there can be duracells in there with "use by 2010" or even ea…
Anecdata, I recently had to replace batteries in several smoke alarms. 3 were Duracells and 2 were Rayovacs. All Duracells were from 2016/2017, i.e. assuming they were installed right away they lasted around 5 years. Rayovacs were from 2010 and 2011, despite both brands being rated for 5 years. It is possible that old Rayovacs were installed around same time as new Duracells and both lasted around same time, still ma…
Eh most smoke detectors are only rated for 10 years, you may want to check those and chuck them based on what the manufacturer says.
Re: Great AA Alkaline Battery Test (2016)
#150Let me leap in here to ding Duracell. They used to be my goto battery, but over the past few years (there was a hedge fund takeover, which IME rarely results in improvements to long-standing quality products) they've turned into liabilities - specifically, they are extremely prone to leaking once even a little bit discharged. To this day I open old kit and there can be duracells in there with "use by 2010" or even ea…
I have a pack of AAA Duracells I just went to open the other day which were "use by 2025" that I purchased just a few weeks ago, and one of the batteries in the middle of the fresh unopened pack was already leaking with one end fully encrusted with corrosion.