How can I maximize the life of a TalentCell's, or generically, any Li-Ion backup battery?

Background: During a recent power outage my ~2-year old TalentCell li-ion battery crapped out after only a couple hours. It had tested out to 5 days when I first got it.

This battery is pass-through, that is, there is no switching when utility power fails. The battery is always topped up.

The little light on the charger is always green, which I guess means it's not charging. Whereas, the lights on my modem and router are red. It ran the modem the other day in a test to 25% for 12 hours, as I recall.

Right now, the hub's been two days on battery, with 3 lights (75%) still remaining.

How can I prolong a li-ion battery life, specifically in this TalentCell?
Should I let it run down some (no flat line) once in awhile?

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Lithium ion batteries don't like extremes; though they'll eventually lose capacity regardless they retain more of it for longer if you avoid running them flat and avoid charging (and leaving them sit) to 100%. A new laptop I got recently has a 'normally left plugged in' mode and it won't charge the battery above 80%,.. and AFAIK most Li-ion batteries have internal protection that prevents them from discharging to zero (bebcause if they do, they won't recharge at all),

Some good tips here: Tips for extending the lifetime of lithium-ion batteries | University of Michigan News (


Thanks very much. That's probably what happened.

I guess a smart plug could be used if you knew where 80% was.
Maybe just run it a few hours every once in while with a rule.

Thanks again. Will have to read up more.

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Just wanted to say thank you for sharing your experience with this. I'm in the middle of trying to put battery backups on my router, C8, and some security cameras. The more I look into it, the more problems I see and it's pretty much all related to your issues of battery longevity and sitting at full charge + being constantly charged for the entire life. I have APC and Cyberpower lead acid UPS units that all seem to degrade over a few years to a unusable state, so I'm worried about lithium ion or lipo stuff as well.

I've been thinking of the same possible solution as you, using a smart plug to intentionally force a battery drain. Not a huge fan of this solution, but I don't see other options so far. I just don't like the idea of having to regularly cut the AC power to critical stuff even if there's a UPS to catch it. From a battery health perspective, I'd probably want to drain the battery down 30-60% each time and if I wrote that into a rule, I'd have to hope that level of discharge is still enough to keep the system up after 1-2-3 years.

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Have you come up with a plan, or found another better mini ups?

As I said, I have three TalentCells: one each for the modem, router, and hub. The included transformers for the modem and router are each around 2 amps, maybe a little higher for the router. The lights for those on the TalentCell transformers are usually red although the batteries do seem to get charged. These units lasted pretty well.

The one that died early was the one supplying the power-sipping Hub. Its light was always green.

I might try to run the three backups on two chargers and daisy-chain the hub ups into the modem's ups. Maybe the ups (battery) normally just devoted to the hub will work a little harder.

Maybe cycling the battery's charge duration with a smart outlet would help, but I wouldn't know where to begin, and if it would indeed do any good.

If my plan works, maybe the battery powering the hub won't die a premature death. The downside, it won't stay powered up as long on battery power since it'd be sharing with the modem. Maybe around 12 hours instead of 5 days.

Reading the Amazon reviews on the TalentCell Mini UPS, maybe people have had theirs dies after a year or so of UPS duty. They typically would find out just when they needed it...during a power outage.

I got tired of trying to find other pass through charging battery packs, so I just ended up buying the little Talentcell 3000mah packs. I have the battery pack ac adapter plugged into Zwave smart plugs and a rule to shut off ac power every month for 4 hours to put some draw on the batteries. I'm still working on figuring out the right amount of time to switch off ac power.

I'm also trying out the same strategy on some new lead acid Cyberpower UPS as well to see if I can maintain the battery. My solution is kludgy, but it's better than nothing I guess. I really wish there were some smarter battery backup solutions out there.

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It'd be to know what I was doing, lol.

As I said, a frequent refrain in the Amazon reviews, as well as my experience, its failure is only notice when the unit is needed, during an outage.

I fully believe these little Talentcell UPS are going to have battery failure at some point in their life. They don't have an advance charge controller and bms, so they just sit at near full charge the entire time. Lithium ion 18650 batteries make up the guts of these UPS and those are well known to not like sitting at full charge their entire life. I've dealt with plenty of swollen lithium batteries as well. I was trying to find UPS containing lifepo4 because they fail in safer ways, but didn't find anything to meet my needs.

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Talentcell has one of those too.

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I have used the TalentCell battery pack on a wearable project. I used this because of the size and power available. The 9v port supplied 3A compared to the USB 5v @ 2A. I lost some efficiency with the buck converter but overall it worked well.

I am updating that project and using a new controller that has a USB-C connector so I am switching to these battery packs.

They have the same capacity as the TalentCell packs I was using but are smaller. They don't use 18650s so hopefully they are a bit better cell. It also has a % readout so you can get a better feel for how it is discharging.

With all that said I also picked up a much larger version from the same company. I just installed it on my C8p so I don't have any performance data yet. It has three USB-A ports so I am hoping I can run three hubs off of it (C7, C8, C8p). Right now I'm using the C8p's power supply so I'll need a beefier supply to run all three. I'll look at that after I test it out with the single hub.

This still doesn't solve the always on issue but it does use cells similar to laptop batteries so I'm hoping it will be more reliable than 18650s. Plus they have a 50% coupon so it only costs $18 -- cheaper than their smaller pack!

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Fantastic. Thanks for the links!

I'm tempted to get some, but I probably should wait until the TalentCells, or at least one more, are DOA.

Looking at the descriptions, it seems to me that the little one says it supports pass-through charging, while the big one says nothing about it. This is necessary for UPS duty. What do you think?

Edit: In fact doing a search on "pass" for the little one, I get only one hit of a dissatisfied customer.

I'm not really sure. I bought them for my other project. I think the small ones will work just fine so I decided to try the larger one as a backup. I guess I should look into it more. :slight_smile:

As I recall, finding ones that do pass through is not that easy.
At least the TalentCell does that, lol.

Looking at another thread there is a flaw with this battery. While it does work while plugged into power it turns off the output for a second when power is removed. That isn't a problem for my coat but it definitely isn't good for Hubitat. :frowning:

Oh well, the larger pack fits (just barely) in my inside coat pocket. So I'll still have that in case I decide I want to run the lights for days. :wink:

The little one?

They both have that same flaw. I use the little ones for my Sonoff dongle repeaters and they are great since I am not worry about lost of power when switching. They used to sell the 2 packs for around $25 bucks on sale.
I wouldn't use it for the hub though. I am also using these batteries below for my zigbee sensors.

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No, I had the big one plugged into the C8p.

I just tried the small 10,000 mAh pack with my lights and it does the same thing. When it is running if I unplug the power the USB ports lose power for about half a second. When I plug power back in the USB ports again lose power but they go on and off three times before settling down.

Not a problem for my coat since it will never be plugged in. Obviously not good for Hubitat.

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