Rechargeable Lithium 1.5V AA cells.

Simon Simple snipped-for-privacy@nottoday.co.uk> wrote in news:10di583$36qi6$1 @dont-email.me:

I have some AmpTORRENT ones that faired well in a test by what appeared to be a competent youtuber.

I use them in a motor application (pepper grinder) so have no experience of them in a low drain situation as yours is likely to be. I did however just measure the open circuit voltage of one with a high impedance multimeter and it was bank on 1.5V so clearly the little switcher is on all the time in standby and doesn't need a load to start up. I've probably had them in use for a year and haven't had to recharge them yet.

These ones have a separate (4 way) charger that runs off a usb type connection which I would prefer to a built-in usb charging point on the cell, less faff.

Ah, sadly unavailable from Amazon:

Here's a link to a random cell tester on YT:

What's the matter with NiMH?

I need 6V, 4.8V is too low and the battery holder holds four cells.

AIUI. NiMh tend to have lower voltage.

I have a laser thermometer which didn't work well with 9v NiMh, but has worked with 9v Li rechargeable. I presume it is the same for 1.5v AA.

I've been using some charging-socket-on-the-battery EBL AAs for a couple of years on wall clocks. Seem fine - last about the same as alkalines.

Recently bought 10 EBL AAs with a charger - all measured 1.5V. Been in use in various things around the house but too early to tell for sure how good they are. Quite pricey - about £24 for 10 including the charger (Amazon).

Having used Ni-MH AA batteries (8 off) in a wildlife (aka Hedgehog) camera for several years, I bought a set of Li-ion batteries and used those for a couple of years. They are the type which have a USB socket (leads supplied) for charging.

Note: That model seems no longer available and the nearest equivalent seems to be: "EBL 1.5V Lithium AA Rechargeable Battery - 3500mWh High Capacity with

I liked them a lot more than the Ni-MH, since they lasted much longer without the voltage dropping below the point where the camera (& IR lighting) stop operating. The Li-ion give 1.5v for the whole time & then fall off a cliff.

I eventually got fed up of having to go out and collect the SD card each day to copy off the video[1], so I now have a POE 'Security' camera set up which saves a lot of hassle. The one drawback is that I could easily move the trailcam anywhere in the (fairly large) garden whilst the security camera is a fixed installation.

Just by the by: we have a Garde Pro Trail camera which we got 4 or 5 yerars ago to watch for hedgehogs (therefore: 8 to 12 hours infra-red triggered observation).

This requires eight 1.5V batteries. I got fed up with them running out, and having to buy more[1], and changing them, so I looked on eBay, found a mains adapter for this camera (which has a standard input for power), and it's been maintenance-free ever since: a great trelief, because it's enough of a bind just checking through all the bloody pics for signs of life!).

Of course, I also had to work out a way of running a cable to the camera's power source. which I managed OK. It's run for 2 or 3 years by now.

HTH AJ [1] PS Rechargebales were not so good. I emailed Garde Pro and they actually replied(!), telling me that Alkalines would be best. (no idea why - I don't understand electricity). I used to buy Tesco's own Alkalines, which were pretty OK. But the mains adapter is about 3000 times better - and NO trouble!

They likely specced Alkalines, just to meet their stated 1.5V-per-cell requirement.

They would say "let's see, what chemistries make exactly 1.5V". Alkaline made the list. And is available widely.

The mains power source, is an excellent solution, as it is less likely to fail to deliver, if the temperature drops below 0C by a little bit.

If you built a chain of NiMH, until you had 12V or whatever the external input jack says in voltage, the trail cam may not have "Low Voltage Cutoff" behavior. If the trail cam had been specifically designed for NiMH, it might "disconnect itself" when the battery chain dropped below say 10V. If it does not protect a rechargeable battery chemistry, the life of the cells may be reduced or a cell damaged. If batteries are reversed biased, some of them plate out the primary metal, which is bad for them.

As for the lithium-1.5V-emulator cells, I would be very careful about using them in circuits. You really need a detailed datasheet for those, to ensure you are using them properly. Do they need low-batt-cutoff devices for their usage ? And so on. The description so far, seems to be almost ideal behavior. But it's better for the manufacturer to tell us what not to do to them. For example, putting too many of those in series may not be allowed. That is why I want a datasheet.

Paul