Lithium is even more reactive than sodium. When I was in college chemistry class, we cut off a tiny piece of sodium and dropped it into a metal beaker of water. The sodium reacted immediately with the water, disassociating it into hydrogen and oxygen gases. The heat of reaction was high enough to ignite the hydrogen causing an explosion. Had the metal been Lithium or had the quantity of sodium been larger, the explosion might have been quite destructive.
Rechargeable Lithium ion batteries such as used in cell phones and electric vehicles are highly flammable. That is why they are not allowed in the cargo hold of airplanes. They have to be transported by ground or sea. Rechargeable lithium ion batteries should always be recycled, never disposed of in the trash.
Fortunately, the non-rechargeable lithium cells such as Energizer Ultimate Lithium AA cells or coin cell batteries contain only a very small amount of lithium. The quantity is such that you can dispose of expended batteries safely in the trash. I do not recommend tossing any battery into a fire as pressure can build up causing the casing to explode.
Keep in mind any legit Li-Ion batteries have protection in them to prevent fires. There is a thermistor to measure cell temp and typically a one-time fuse. If you let them die down until they are right dead, typically they won't even recharge because of the fire protection.
Now, if you replace your Li-Ion with some econo priced unit off Aliexpress, then all bets are off.
Bottom line: All Li-ion batteries are inherently dangerous to a certain extent, just like propane/hydrogen tanks, mega-capacitors, gasoline, ammunition, etc. Anything that stores a large amount of energy in a small space should be treated with utmost care and a healthy dose of caution.
If you want to go full on "wear the tinfoil hat" then I'd assume that you charge your laptops, tablets and phones in a steel garbage can in the center of a concrete driveway with fire extinguisher present. Those have Li-Ion, a laptop has more than any tool battery.
Everything has a failure point. My brothers upstairs toilet had a mfr defect and it cracked when he left for the weekend and flooded his entire house. If you want to carry "being safe" to the maximum, then turn off the water and and main breaker to your house when you are sleeping or away.
Of course I have many Li-ion batteries in my house. But I don't leave any of them charging while I'm away on vacation, just like I turn off my gas and water lines when I go on vacation. I cannot ever eliminate all risks, but I do try to minimize them whenever possible.
I won't complain about them because their support is good. They replaced my unit when it failed. But after the correspondence with them I realized that I couldn't really use those power strips for anything useful. I have two new ones still in boxes because they don't support any of my applications.
The Zen20 is a power strip. Thus, it should not be used with high-power draw devices such as appliances and motor driven devices.
I can see some logic behind not using it with a large battery charger such as is used to charge a car, marine, or golf cart battery. I do not see any reasoning not to use it with a USB charger for a cell phone or tablet.
Likewise, a WiFI router is a low power device. If you wanted to power off your router periodically to reset it, why would the ZEN20 be unsuitable. I have used 10 amp Zigbee plugs for this purpose without issue. Does anyone know why routers are on the unacceptable list?
From explanations they've provided elsewhere, it seems more likely that (aside from amp/Watt ratings, which do come into play for some of their devices) the issue is frequent on/off cycles--e.g., as a phone reaches full capacity, the charger may alternate frequently between charing and not, which apparently do not play well with many of their smart plugs according to warranty claims they've received. Not only that, they didn't like that my laptop was chariging througn one.
On a related topic, this was their explanation for why they included USB ports on the ZEN20 power strip, for example, so you didn't need to connect a charger (now, if only they were controllable!).
maybe they are referring to a wood-working router? Power tools use electric motors, which can have very large in-rush currents. Most everything on their naughty list has an electric motor in it.
Lost my first Zen 20 to an inkjet printer (65 watts at startup) and my second one to a 36" tv. The wifi power strips that replaced them have handled everything I've thrown at them.
On a somewhat related note, I found a swollen and
cracked Zen25 last week and it's never had a load plugged into it.
Wow! That power strip seems almost useless, IMHO. I prefer a traditional mechanical relay (with the audible “click”), for smart “switch” devices. Much more robust for a variety of loads.
If they aren't using a relay, then they use a TRIAC to turn the power on/off. You cannot use a TRIAC on inductive loads (motors, pumps, certain switching supplies). That's probably the reason they state that.
I put Lutron switches in my house, and the dimmable ones got really angry with the 12V ballast driven undercounter lights. I had to install one of their "relay" versions for fans for that application.
Unless you are unplugging them when you leave for work as well, it's basically pointless. If one ignited 30 minutes you left your home, the house is a total loss in under an hour. Just saying...
Not saying the idea isn't cool as heck. Cooking Li-Ion by perpetual charging kills them.
I work from home, so I don't really have to unplug stuff very often. But fortunately, now that I have a Hubitat, I'm in the process of adding Zigbee plugs on all of the outlets in my house with Li-ion devices plugged into them, so I can set them all to turn off when no one is home.
I'm content with my use of these despite the do's/don'ts list. @bertabcd1234's explanation of Zooz's apparent logic and his later quote from Zooz, indicates to me, that my use case isn't really an issue.
My power tool batteries, are not frquently cycling (active/dormant) on their chargers, my charge time is short (30 mins as I recall), and I don't really fear the battery packs melting down on me.
So far, I've had one failed Zooz power strip, and it wasn't one with chargers attached to it. Wait -- it did. 1 Logitech Harmony Remote Base...well there ya go. And that charger was on all the time, unlike my power tool battery chargers.
Interesting.
In truth, I'm more fearful of the two crazy complicated Tesla batteries in my garge melting down and burning my house to the ground than I am some tool batteries...lol
