Actual 1.5v AA rechargable batteries with built in bms not 1.2v for locks and such

I came across some Tenavolt rechargeable AA batteries. The batteries actually contain a 13430 3.7v 750mAh 2.78Wh Li-Ion battery and a built-in bms to maintain a constant current of 1.5v. Just thought I'd bring this up for people with locks and such since they behave better at 1.5v rather than 1.2v that NiMH rechargable batteries put out such as the Enloop batteries that are so popular.

Here's an amazon link to the batteries.
https://amzn.to/3kWuxOg

Here's a good video of a teardown for the battery.

Here's a good review of the relevant information about the Tenavolt batteries.

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Just what I was looking for, Thanks for the info perfect timing too! I wonder if My opus BT-c3100 would be okay charging them?? Charger shouldn't make a difference?

Yea, I bought 20 of them along with the wall charger. The charger build quality surprised me. It's powder coated and has some heft to it, I was expecting a crappy plastic one.

Charger does make a difference. The bms only plays nice with their charger.

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Mind reader I'm telling you lol

Both trying to solve the same problems it seems so not surprised.

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I use eneloop and they show up at like 75% when fresh and seem to drain pretty fast. Ended up using lithium but they seem to just go from 100% to 0 with no notification

Yea, these wont get around that either since the bms maintains 1.5v until the battery cutoff level but they're rechargeable and I have a bunch I can swap out at regular intervals.

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I am very interested in this. Any idea how long a set of 4 will last in a deadbolt or lever lock between charges? I am doing the math here but I have 7 locks to feed which would be a pretty big hunk of change but will do it if they will run for 8 months or more on a charge. Right now I am changing out double AA's every 6 months. So two hundred bucks to get set up with these vs. approx. $15 every six months with alkaline's. If I am pulling them every 6 months either way I don't know about pulling the trigger on these.

This is awesome! I never knew those types of batteries existed.

I found several similar types and decided to try the EBL branded ones (They were 10-20$ cheaper in Canada). Ordered one set that comes with a charger, and another that have micro-usb ports and charge directly from there. I’ll provide an update once I tried them.

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This is worth checking out to see the varying quality levels.

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I came across a bunch of bad reviews on the ebl batteries. I went with the tenavolt batteries not because they had the highest capacity but because of all the reviews and feedback from some coworkers that have been using them themselves for a couple years.

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That sounds like a good plan!

At $12.50 per battery and not Prime, I was concerned with the value... though I came extremely close to getting them! I’ll let you know how I make out with the ones I ordered. I have one of my locks that is particularly hard on batteries, so they will go in that one to see how long they last. Currently, rechargeable batteries only last a few weeks in that one, where non-rechargeable typically last a few months.

Yes, I am very surprised at how long these last in my Schlage BE469. I get about 6 months, which is surprising, I expected less. If the lifespan is 3 years they should save almost the entire cost

This is typically a sign that the lock is in high power mode, usually caused by a slight misalignment of the door. You can usually tell by how loud the lock operation is when triggered.

It could also just be hitting the low voltage cutoff sooner. 4 typical NiMH batteries have a nominal voltage of 4.8v while the lock is expecting 6v. That would put the low voltage cutoff for the device around 3.8-4v. NiMH start off much closer to that low voltage cutoff so you typically don't get the full capacity of the NiMH battery before hitting the device low voltage cutoff.

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I helped someone with their lock a month or so ago... batteries only lasting a few weeks... The lock was going in smoothly, no issue. The lock wasn’t deep enough! So it kept forcing every time it got locked... They drilled the hole further and problem fixed!

In my case, I think it is an issue with the low voltage cutoff. It has no issue closing, but keeps beeping after every lock after a couple of weeks. I had another model of lock in the same spot before that had no issue, and can confirm it slides in well.

I’m eager to see how well it will work with the new batteries!

I had this same problem at my old house. Just drilled it out and it fixed it for me as well. Luckily in the new house, everything lined up perfectly for all the doors so no fussing about was needed. If anything they open too easy now. The twins manage to unlock it all the time now when they're being super sneaky.

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I was lucky! My twins never tried to sneak out... That or I never found out... :wink:

Soon as one cracks the door open the other one bolts for the door too. Which is usually my que that one of them got the door open.

Haha! Yup, that’s how it goes! And when outside, when one goes right, the other goes left.

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