Blackout? A primer on rechargeable batteries

Turn Aa Cells Into C Or D Cells

These work
Check this out on eBay!
Battery Buddy AA to C/D ADAPTER


Rechargeables In Garden Water Control Timers

I purchased a Powerex charger for AA and AAA batteries so I could have a bit more redundancy for my garden timers. The charger works fine but the batteries themselves were not reliable in the timers.
Further checking revealed that the Rainbird timers recommend NOT using rechargeables apparently due to the lower charge level. I have not tried the Tenergy battery.
For the moment I am using Duracell as I really don’t want to risk losing a crop to a failed timer battery.
Meanwhile, my gophers always seem to have a full charge!


Also oil lamps, lamp oil and wicks.



Teenagers may be the best teachers of the utility of reliance on batteries. I have lost count of the number of “rechargeable” units that have gone to recycling (or the dump). In my days living off grid with solar/battery systems, there are a host of mistakes possible, and maintenance is a thing.


Nimh Batteries

Something that I have found out about Rechargeable Batteries is worth mentioning. It has to do with Nickel-Metal-Hydride (NiMH) batteries and how they handle a highly inductive load.
I had a Rain Bird automatic timer for the Garden Hose for scheduling the irrigation. Once the original Alkaline Cells needed replacement I charged up two NiMH cells ( AA size ) and put them in.
The next time the unit tried to open the water valve, it did so, but did not shut off after the watering period so I went to find out why.
The battery compartment was steaming vapor, the plastic had fused shut, and the whole thing was screaming hot. I pried the battery compartment out with a hammer and chisel and managed to separate the batteries from the unit itself.
The circuitry had self-destructed, as well as having the two nearly-melted NiMH cells. The issue as I have come to find out is that NiMH cells do NOT want to handle the high instantaneous current pulse necessary to open or close a solenoid.
I expect the same precaution relates to other devices as well, such as Relays, Motors, and Solenoids – anything which drives a strong current through an inductive load.
– Chuck


I’m Over Duracells…

I never remember it being a thing in the past, but I now consider Duracell batteries to be destructive to all things to which they are installed. I can’t tell you how many things- expensive test meters, various recorders and radios, household devices, flashlights- I’ve had to toss due to battery leakage. Who really has the time to monitor all those gizmos constantly for battery condition? I’ve even had brand new packs of Duracells- “ten year shelf life”- leak when in storage a couple years. Sheesh…As a stop-gap, I’m leaning towards removing batteries from everything I don’t use almost daily. Kind of a hassle…I’m considering transitioning more towards devices that use the 18650 style lithium battery. This is probably the type battery that is in your little USB charge pack, cordless drill, or nose-hair trimmer ?. They tend to hold a charge for a long, long time. They do require a more involved charging process and charger, but I’ve never had one leak, and they are generally higher capacity than any other rechargeable. 3.7v, so more in keeping with the ubiquitous “5v USB” that powers so many devices these days. I got this amazing Hybridlight 300 a couple years ago at Costco that came with an equally amazing little “camp light”- the model PUC. I’m guessing- because surprisingly I haven’t taken them apart yet- they have the 18650 battery in them because they offer USB charging, in and out. I’m exploring this battery more, as I have access to some “failed” battery packs from power tools, lawnmowers, etc. The batteries are mostly good- the internal pack circuitry usually fails. But this is a kind of DIY project that’s not for everyone…Aloha, Steve…


Regarding leaking alkaline cells … you are absolutely right.
They have resulted in countless ruined devices.
I did find something that is useful to attempt DIY repair on them, in some cases at least.
Lee Spring Company has some battery contacts that are made for AA and AAA cells. There are several alternative choices. Here is what I bought.
The springs are made from Beryllium Copper, and silver-plated so they can easily be soldered - which is not possible with steel springs.
If you have a drawer full of dead remotes, calculators, and flashlights, it’s worth your thinking about.
– Chuck


Yes on the 18650 batteries. Very powerful generally, very few failures for me over a decade. Can be used to refurb portable tool packs if you are skilled.


You had me all excited for a moment there, Chuck. But $9 each in small qtys? I’d be likely to try this first. Undoubtedly not the quality of Lees, but…Aloha, Steve

Batteries With Direct Usb Charge

This brand of battery has a mini usb charger right in each battery

A friend of mine runs a Bed-and-Breakfast, and each room has a battery-operated Safe for valuables, and an A/C remote.
I justify what is [admittedly] an exorbitant expense by the fact that in many cases I can turn that $9.00 and a few minutes of soldering into a case of beer.
Just saying …
– Chuck

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There you go! Just shows how a person with skills will prosper in the coming times. Good on ya, Chuck! Aloha, Steve


12v Battery Cycle Life

You failed to mention the battery life comparison for lithium and lead-acid
Lithium batteries last much longer (more charge - discharge cycles)
So you can buy cheap lead acid batteries and replace them every 5 years, or buy expensive lithium batteries and replace them every 15 years.

My Thoughts

The 12volt solar off grid batteries - Lithium has only pros and very few cons compared to lead acid.
LiFePo4 lithium batteries are very safe, they are not in normal use a fire risk.
For example they do not catch fire on over charging. The only way you will get a LiFePo4 battery to ignite is to puncture the battery cells with something like a nail or to set it on fire by other means.
As we enter an age of scarcity, the fact that you can use 90-100% of that advertised 200ah capacity in a lithium battery and get 2000-4000cycles out of the battery with still life in it, is the main selling point.
The cheap FLA or SLA batteries allow 40-50% of the capacity to be used and are generally knackered by 500 cycles, if not before.
The only thing going for lead acid batteries these days, is the cost and that is not a reason to purchase them. Also I have seen a fire started by an exploding lead acid battery in a battery bank.
Jackery make very good all in one powerpacks (solar generators) and it’s great that you meantion them, as these kind of power supplies offer a great way of having some back up 120v energy without the need for a generator.
I prefer Poweroak, which are branded Bluetti in the US, they use LiFePo4 cells and have a longer overall life. Also judging by the Amazon reviews of both companies products, Bluetti seems to have a lower failure rate.
The main problem I see at the moment (seems to be more of an issue in the US, than Europe at the moment) is getting hold of a Jackery or Bluetti solar power generator!


Standard NiMH rechargable batteries have a 1.2voltage instead of the 1.5v that you get with a non rechargable Duracell AA battery. There are some lithium rechargeable AA batteries available that would give you 1.5v and a long standby life - they are recharged using a usb lead.

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Those dates are sketchy. Pulled same Energizer Lithiums out of their original packaging for use with years to go on them and they barely lasted 2 months in a 2 year estimated use for the device they were in. Just an FYI.


Battery Life

I have noticed that batteries last way way longer when you remove them from the device, when you are not using it.


Compensation For 1.2v Of Nimh Batteries

In couple of devices that use 3 batteries 1.5V ones I install external bank of 4 1.2V NiMH batteries.
So far I did not have any problems that 4 fully charged batteries can have initially 5.4V or even slightly more instead of required 4.5V
Brand new 1.5V batteries initially have little bit more than 1.5V too.
Externally fitted batteries are bit cumbersome and look clumsy, but on a plus side save against internal leakage.
Also if external power bank has ON/OFF switch it is so easy to turn it to off position every time when device not used.
So far I did not use 3 batteries 1.2V instead of 2 batteries 1.5 volts.
Did anybody experiment with this configuration?

I know of a case in which an approximately 1 MWhr lead acid energy storage facility at a wind farm caught fire and burned up more or less entirely. You can only imagine the toxic contamination problem from that!

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Don’t Forget Faraday Storage

I store my electronics in a converted steel trash can to shield my electronics from a EMP or CME.

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