Ecolink, White Dual Rocker Style Light Switch battery reporting issue

I purchased a ZWAVE Plus Ecolink, Lighting Control, White Dual Rocker Style Light Switch Design (PN - DDLS2-ZWAVE5 in January from Amazon.

The pair connected well and work well with my Hubitat C7 and now C8 hubs. I bought these because I’ve been very happy with my Ecolink Tilt Sensor which has worked well for years on a single battery.

I’m having issues with the battery reporting on both switches in this set. Weeks after installing, the included batteries showed a sudden drop from 100% to 0%. I attributed this to the possibility that the included batteries might have been weak from age in the box and replaced both with known fresh alkaline batteries even though the allegedly dead batteries tested within spec.

Now, just a few weeks later, it’s reporting 0% again… but the switch still responds to ZWave commands. Thinking that it may not really be the batteries, I persisted with those same batteries, only to see them later again return to reporting as 100%. This has happened several times. The same batteries reporting 100, then 0, then 100, then 0… currently showing 100.

When the switch is reporting zero, the red LED lights up and is visible through the cover plate during ZWave commands. Then when it returns back to 100, the red LED doesn’t illuminate. I suspect the issue is in the switch battery detection.

I contacted Ecolink and there is no firmware update available to correct this behavior. Is there any alternate device driver for Hubitat that might address it? I’ve tried Any ZWave Switch from HPM.

If the device itself is reporting 0% battery as indicated by the red light on the device, then I dont see how a driver would fix it?

A lithium battery will hold its voltage longer, and hopefully report 100% for longer.

Thank you. That was my thought too, though Ecolink thought a different driver might correct it by interpreting battery info differently. They say batteries should last:
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“ In testing with Alkaline batteries we were able to get between 700 and 1000 cycles before battery level became low. With a use of 2 times a day that equates to between 350 and 500 days (real world use will be less). Lithium batteries will last longer due to their higher power density.

However, when it comes to reporting, some hubs interpret the signals they get from the z wave stack differently. Most will indicate roughly 4 states of the battery which roughly correspond to Brand New, Good, Low and Extremely Low/Dead. The percentage displayed is often confusing, for example, some might show 100% (Brand New), 99% (Good), 1% (Low) and 0% (Very Low) while others might show Full, ¾, ¼, 0…etc. What was unusual about yours is that it went from Very Good to Very Bad then back to Very Good. Which makes me think there is something weird in the way the Hub is interpreting the charge. I would go with your idea and try the lithium batteries and see if that helps the reporting, it may not, but even if it doesn’t you should still get several months use out of the device with fresh batteries. ”
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I’ll try lithiums. If they don’t last, Ecolink has said they will replace under warranty.

I’ll add here that Ecolink support responded very fast and has been communicative and helpful.

The main thing that makes me think it is the device is you said there is a red LED that lights up. I highly doubt the hub is telling the device to light that LED up, the device is doing that on its own because it thinks the battery is low.

Also, the device should be reporting standard zwave messages, in which the battery would report a percent from 1-100%. There is no way the hub would confuse this as anything else, its a number, there is nothing to interpret or confuse about it.

Unless this device is reporting the battery voltage instead of a percent, but have never seen this done for zwave and I don't think its in the zwave specs so it seems unlikely.

Thank you.
I’ve measured the voltage of the batteries at 3.117 VDC for the 2 AA batteries.
The mfgr says 2.7 VDC is the threshold for low battery LED. I’m communicating with them about it.

Likely will ask for replacement as I don’t want (another) battery hog.

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