My Scheme for Doubling the Lifespan of ReSound Quattro Li-ion Batteries

Thanks for the tips! Tip #3 sounds like a good source for backup HA’s if I get so used to my HA’s that I don’t want to go without some if either of my new ones have to go back to the factory for evaluation, service, or replacement and my audiologist doesn’t do loaners.

Aiding my controlled, incremental charging scheme to get the most out of my expensive Quattro Li-ion batteries is the fact that when the HA’s are in their charging case charging, the ReSound Smart 3D app on my phone can be used via BT to read the charging state of each HA separately in 20% increments. This is handy because the charging case itself only indicates the % charge of the least charged HA of the two and also 10 seconds after inserting the HA’s to be charged, the LED indicator on the charger times out and one has to remove the HA’s from the charger case then to access the charging state of their batteries via the case LED display, whereas the Smart 3D phone app allows continuous monitoring of the charging state of each battery separately.

I’ve discovered a few funky things about charging my rechargeable ReSound LiNX Quattro 9 61’s that anyone else with the HA’s might find useful to know or might find behaves differently and want to contrast their experience.

First of all, the behavior of the bank of 5 charging LED’s for the HA itself, represented in the Smart 3D app and on the front of the charger case for charging the HA’s. Discharging the number of lit green circles seems to represent the state of charge you’d expect. 5 circles lit, fully charged. 2 circles of 5 lit, 40% charged, etc. But in charging ReSound seems to have switched the logic. You start out at 2 of 5 circles lit, you charge to just over 3 LED circles lit and the 4th has just started to flash. So you think, OK, based on the way things went down during discharge, you’ve charged to just over 3 circles lit (>60% lit) and you’re working on the 4th charge state (80%) being reached (it’s flashing) but you’re not there yet, because otherwise it would be solidly lit. (This is following charging of each HA in the Smart 3D app). But what happens at this state when you remove the HA’s from the charger and look in the app, you see, according to my interpretation of how the app display % charge when not charging, that you’ve actually charged the HA’s to >80% charge. Apparently, going up in charge, an LED up the charging scale starts flashing ONLY WHEN YOU’VE PAST THAT DEGREE OF CHARGING. I’d rather have a particular LED in the hierarchy only light and stay solidly lit when you’ve passed that level of charge and have the next level light start flashing to indicate that you’re just beginning to work on that level.

The other funky thing is the bank of three LED’s displaying the state of the charging case Li-ion battery that serves as a power pack to charge the rechargeable HA’s. I got the charger case from the audi on Wednesday, 10/24/18, fully charged. The charger case supposedly holds 3 complete charges for both HA’s. Since Wed. at 30 hours of use per full charge, I estimate I have done the equivalent of fully charge my HA’s 1.5x to 2x, yet the LED’s on the charger case still show all 3 LED’s fully lit when I insert or remove the HA’s Theoretically, at least one of the 3 LED’s should have gone out by now as I should have used at least one full charge from the case (I haven’t charged anything on AC yet myself).

So I’m a sample of one. If you just charge your HA’s every night, maybe none of this makes any difference because you’ll charge both your charger case and the HA’s fully but if you need a quick charge and want to know where you’ve actually charged to as the HA’s are being recharged in their case, knowing about the funky behavior that I describe about the 5 HA LED charge indicators might make a difference. Also, if you’re counting on the 3 charger case LED’s to accurately reflect the charger state of charge when used as a power pack, you might go out the door with the charger case with 3 circles lit thinking it’s full of reserve charging capacity when it’s not if you haven’t fully charged both HA’s and the charger case overnight.

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Ok, now read this and relate it to your experience in charging and displayed charge level. :crazy_face: :joy:

Battery University is a techno-weenie geek fun house!

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Oops! MY BAD! I am an RYFM type, Big Time. The LED indicators for the HA’s do not indicate a level beyond which you are past. The LED indicators indicate a RANGE. So even if all 5 HA LED charge indicators are lit, that only means your HA’s are somewhere in the range of 80% to 100% charged, NOT 100% CHARGED.

So charging past 3 fully lit LED charge indicators with the 4th flashing, then having four HA charge indicators fully lit when I’m done, according to the declared ReSound behavior, means that I’ve achieved a charging level of 60% to 80% charged, which is exactly what I expected. And starting to charge from 2 of 5 LED’s lit doesn’t mean that I started above 40% charge. It means my HA’s were somewhere in the 20% to 40% charge state. So that’s good to know if you go out the door thinking your HA’s have >40% charge (2 of 5 LED’s lit) but they actually are just above 20% lit (and one green light means 0 to 20% charge!).

From the Quattro 9 61 manual:

Also, here’s the Quattro 9 61 chart for the charger case itself. The LED light indicates a RANGE, not a charging level past - but I still think that I’ve used more than 1 of the charges in the case and only 2 of the 3 LED’s on the case should now be lit after 5 days of HA use and charging only from the case.


Yes, I’ve followed Battery University for years and that’s in good part where I’ve derived my Li-ion battery use and storage “protocols” from. Apple also has good advice on the expected lifetime and device storage for their Li-ion battery-powered devices. And I’ve skimmed through various research papers on Li-ion batteries (the Android app AccuBattery is based on one particular research paper).

The catch with all this stuff is, how current is the knowledge expressed in any article, website, and what the heck type of battery exactly is in my particular device. Some of the advice on the Battery University site seems kinda old and I think they do claim in general that the general chemistry/behavior is the same across all Li-ion powered devices whether it’s truly Li-ion slush or Li-ion polymer, etc.

The advance in Li-ion battery chemistry that I’d most like to hear is that it’s now safe to charge below 55 deg F. The Quattro’s claim from the manual is: " If the hearing aid temperature is below 0 °C (32 °F), it will not charge immediately. Charging must take place between 0 °C (32 °F) and 40 °C (104 °F) ."

I’d like to know how “safe” the high and low temperatures of the charging/operating range are or what kind of price you really pay on the lifespan of your device for operating at the stated extremes. Unfortunately, HA manufacturers seem to follow the KISS principle to the extreme, perhaps both not to reveal potential weakness of their devices relative to their competitors and not to confound old folks who don’t like new complexity injected into life.

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BTW, Tim, if one just skips most of the article and goes straight to the Summary and Guidelines at the end, there is some simple, straightforward advice on dealing with Li-ion batteries in easy-to-understand language. I recommend reading that part and skipping the rest!

Ok, sorry, but I’m going to have to ask you to turn in your geek card.

Summaries are never enough for me, I want the down and dirty complete intimate details.

Disposable batteries are sooooo boooooring :grin:


Well, perhaps you won’t like this other Battery University article either then but I think the rightmost column of the table down in the article on charging/discharging Li-ion batteries does a good job of summarizing the kinds of rules I’m following in trying to cheat the battery tax collector on the lifespan of my Quattro rechargeables. The fact that the fifth LED in the app display of battery charge state actually starts flashing when the charge state passes the 80% mark is actually rather handy in following the advice “stay below 80% maximum charge to prolong battery lifespan.” Theoretically, in only charging up to 80%, I’ll still have 24 hours of battery life for my HA’s without streaming (30 hrs at 100% charge x 0.8 = 24 hours at 80% max) or 19 hours of battery life with 9.6 hours of streaming (80% of 24 hours of battery life with 12 hours of streaming if done from 100% charged). Whether this is actually worth doing or whether the HA’s should just be refurbished if the need arises was discussed earlier in the thread but I’m just pursuing it as a game - some people like bridge, some chess, some hunting, fishing, boating, golfing, some watching sports on TV, etc. I like testing first-hand whether the advice of folks like Battery University actually works.

I still like to read the entire article, then go to the summary. Most of that exercise is to keep challenging my brain. When I was younger I had almost aphotographic memory and incredible retention from reading. Learning was easy for me, and I only had to study hard on really complex technical subjects. I’ve lost much of that with age, so reading technical info challenges me, and I will spend time cross referencing terms I don’t remember. One of my versions of playing a game.

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I think it’s an accepted idea in neuroscience now that the brain only has a finite capacity to remember things and a lot of that capacity is used up by the time you’re in your twenties or early thirties. I’ve also heard the idea espoused that some memories from youth were once very strong, supported by multiple connections and you keep learning new things as you age by giving up some of the many older connections from older memories to make new connections for new memories. Perhaps centuries ago, when folks didn’t live too long on average, filling up their brains with too much stuff was the least of their worries.

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News from Rechargeable QuattroLand:

Last Wednesday, 10/24/18, I walked out of my audiologist’s office with my HA’s and the Quattro charger case fully charged. Since then, I’ve been only charging the HA’s from the case. I thought maybe, if the case hold 3 complete Quattro charges as it’s supposed to and a charge lasts 30 hours, that maybe I’d go a couple days per charge and use up the charge in the HA’s plus the ~3 charges in the case in a week or so.

It was actually 9 days (counting the day I left the audi office) before I used up the initial charge in my HA’s plus 1 charge in the case, according to the case battery level (2 total charges used). That surprises me a lot! Even if I only average 10 to 12 hours of use per day in the intervening time, 10 hours use is 1/3 a total charge of 30 hours, 12 hour use is 0.4 a total charge. So I should have used 9 x 1/3 to 9 x 0.4 or 3 to 3.6 total charges in 9 days whereas if the charge case indicator is right, I only used ~2 total HA charges. (I’m into math!). I streamed about 1 hour each day, too, but had the Phone Clip+ off almost all the time except during the brief streaming period each day and most of the time had my phone Bluetooth off. I was also in a very quiet home environment most of the time so I wasn’t making the HA’s work very hard. So maybe when new, the Quattro charger case actually holds more than 3 Quattro charges?

If the math and lower-bound estimate of usage is correct, I could easily go another half a week to a week before I need to recharge the case and the Quattro’s. The case is palm-sized, light, and easily portable, as another Quattro user has already pointed out. So with my usage/listening environments, with the case as a backup, I can easily go 1.5 to 2 weeks without needing AC. I’ll see how well that holds up as time passes but it removes a bit of uncertainty that I had going with the rechargeable option.

Yes, the battery life for the aids AND the case is quite impressive.

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Just visited the audi for my first follow-up. From the ReSound SmartFit software, she says that I’ve actually been using my HA’s an AVERAGE of 14 HOURS A DAY. So the rechargeable battery life I’ve been getting on my new Quattro 9 61’s is astounding for that amount of usage! She can also follow my volume changes through the fitting app.

So I got to wondering if I turned on GPS geofencing of Smart 3D program favorites, etc., whether the audi and ReSound would be able to collect a lot of personal data about my life, e.g., when I go to bed, get up, go out, where I like to go, etc. I presume that Google and Microsoft and Facebook are already collecting a bunch of stuff but perhaps HA’s are also contributing to one’s Internet data profile to some extent, too. Perhaps folks like @Volusiano and @pvc have already commented on what personal data that HA fitting software can accumulate but if there’s a thread already somewhere on this, I’d be much obliged to get a link to it.

The OPN recently in the last firmware update got introduced with a new feature called Hearing Fitness. “This tracking technology explores the full potential of advanced analytics.” according to their announcement. You can google it more for more details if you want.

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Starkey Livio hearing aids know when you have fallen and can’t get up;

Starkey launches world’s first hearing aid with integrated sensors and AI

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I believe there’s a “feature” in the latest Android, Pie, called Digital Wellbeing.

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Which one is best? Phonak or Quattro?