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Discussion Starter #1
I would like to hear from members about their Bumblebee battery experience. I know from my experience there service and warranty is top notch. I have had my CVT for almost a year. It came with a 2 1/2 year old failing battery due to the prior owner not driving it enough or grid charging.

When I bought the car Bumblebee offered to recondition it for shipping cost only, I thought that was very cool of them. Unfortunately once these batteries loose cells the battle is lost and recovery is a moot point. I grid charge frequently but am sure I have dead cells based off my OBDII readings. Very short voltage range, one small grade will drain it from above 160 to below 150 and throw me into background charging. Assist at 15 amps from IMAC&C will drop the pack by 8 volts.

I’m using Peters tools as an expensive calpod switch at this point trying to prevent assist for long periods that will drain the pack. Even when I use assist during acceleration I don’t notice any difference in the feel of the drive from when it’s disabled.

it’s concerning that a 3 year old pack can be in this condition but I understand the prior owner didn’t maintain and use it as I would.

I don’t believe I have really ever experienced a fully functioning NIMH in the insight. I spend 10 hours a week in my car. I try to shoot for MPG above 70 but a failing pack frequently grid charging with AC use makes that nearly impossible in a CVT even with LB.

If I spring for the bumblebee I will get the 5 year warranty, hopefully that would get me at least 8 years of solid use. I realize the gas savings will not be recouped and many will say bypass. That’s a possibility but I spend over 500 hours a year in my car and driving enjoyment does factor in the equation as well.

What can I realistically expect from a bumblebee, I’m especially interested to hear from anyone that has used IMAC&C with their pack and how that affected it’s longevity. Thanks in advance your your time and response.
 

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I'm not sure about aftermarket cells/packs, but if you had an original I'd tell you to try to use a lower charge state, rather than 'grid charging frequently' or trying NOT to use assist. From what I've seen working with a few OEM packs/sticks/cells, grid charging induces voltage depression very quickly if you overcharge for even short durations, and I imagine it's only worse if you do it often. The flip side of this, too, is that, at least when it comes to Panasonic OEM cells, they need to be discharged to at least 1.1V per cell to maintain favorable voltage performance. The way the OEM battery management works there's probably few cells if any that actually get discharged that low. I think that's probably one of the main causes of pack degradation...

I've been using my pack at very low to rock-bottom charge state for something like 2 1/2 years now, and I've only seen performance improve, hold up longer, way less voltage sag, etc...

I don't really know how to explain it easily, but the NiMH cells seem to operate in weird ways. It's like when new they probably have the capability to perform well across the whole charge state range. But, in time, the pattern of usage can degrade portions of the electrodes, maybe the electrolyte, so that everything needed for proper reactions isn't available in balanced amounts across the whole charge state range. So, capacity effectively shrinks. With OEM cells I've seen that medium to high absolute charge state will quickly erode performance; low charge state usage will bring it back - but you'll have to continue using low charge state.

This is sort of a broad generalization, there's some caveats. But I feel pretty confident about this, now. The main problem is that when cells degrade they most likely don't degrade evenly, and then you have cell imbalance. It's hard to get them back in line so that you can then actually use low charge state for all cells evenly. Most people grid charge to balance, but then we're back to the original problem. To me, it seems like once you have to grid charge to maintain a pack's balance, you're on a downward spiral. I might recommend a grid charge to get some initial balance, but thereafter I'd say drain the pack in-car and thereafter use as low a charge state as the car will allow.

Anyway, all my observations and work is with OEM, and I know the aftermarket cells are at least somewhat different. But, it might be worth at least trying to use low charge state - maybe do a grid charge to get that initial gross balance, but thereafter try to go low and stay low.
 

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My 04 CVT had never been grid charged before I got it in 2013, but I did end up getting a a bumblebee in March 2017. Everything about the transaction was what you would want, not just expected.

The "scoot" that IMA offers was immediately noticeable from what I had before & even now, when I get a new passenger, I like to show off "S-mode" (I won't call it Sport-mode) as it turns the little beast into a go-kart.

If you are averaging 70+ in your CVT, you are doing much better than me, as the Texas heat mandates A/C.

To me, enjoying the drive is as important as getting high MPG's. If you can't resuscitate the pack & you plan to keep the Insight, spring for the "new" pack. Even if you only get 5yrs, you get to enjoy it for the duration vs putting up with a low/non-functioning pack to prove a miserly point.
 

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Well, I'm particularly fond of the batteries we send out.. ;) Except the ones that fail early.. I don't like those ones..

A few thoughts.. You most certainly don't have dead cells; you would have an IMA light. The car is very intolerant of gross problems like that. A dead cell would cause a non-resettable P1568, at the least. Maybe just terminology? The symptom you describe - springy voltage - is internal resistance related more than anything. The IR on your sticks looked fair, at least 9 months ago. How often are you grid charging and for how long? I do agree that the pack isn't the healthiest thing I've ever seen and that the prior use likely damaged it in ways that are hard to quantify.

Background charge is determined by SoC and flags like 12V system load; it doesn't specifically have anything to do with the battery, as far as I know. If the hill you speak of drains the SoC into background charge range(64.9% with headlights on, IIRC), you'll get background charge with any and all batteries. Though of course if you are experiencing recalibrations that cause SoC to plummet, you will obviously be seeing a lot more background charging than 'normal'. Is that the case here? Background charge by itself, while a MPG killer, shouldn't be considered evil. Maintaining the IMA battery's SoC is important.

Your voltage numbers don't seem very bad off hand, but I don't have much context for them. Ideally, you would see around 188V under full regen and 168V after resting for a few minutes, just after the pack recalibrates to 75 or 81%. What does the pack drop to under full assist(around 70A in a CVT I think)? More importantly, what can you get the SoC down to before a negative recalibration?

Regarding low SoC.. I'm not sure how to explain it or how to square it with eq1's observations, but high SoC = good, and low SoC = bad. Universally. I wish every pack came to me with mere voltage depression. That's easy to fix. It's very, very rare that I see any type of voltage depression in Honda packs(with one exception). They allow too wide a SoC range. It's more common in Toyota packs with their much more strictly enforced 40-60% SoC range, but our mild climate puts a damper on it. If you want to see real voltage depression, sample some Toyota packs from Arizona. The one exception to the "Honda" rule is, ironically, the 2nd generation Insight. For that vehicle, they adopted a battery management strategy that might be even more conservative than Toyota's, and it works, but does result in some degree of voltage depression, even in the coldest climates.

Anyway, when Richard's pack came back to me, it was at very low SoC, which matches the description of "not driving enough". I've found that people who take infrequent, short trips are exceptionally hard on the battery; it has zero chance of ever experiencing the rejuvenation effect of the 72% SoC hang.

Here's what it looked like:

85905


The yellow stick with only like ~750mAh would have been the IMA light trigger here. The mAh difference between sticks represents 2.5 years of self-discharge deviation. It's not very much, ~750mAh in this case, but it's virtually impossible to make up any of that ground unless you get up into the 72% hang range.... Or with a grid charger I guess...
 

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Regarding low SoC.. I'm not sure how to explain it or how to square it with eq1's observations, but high SoC = good, and low SoC = bad. Universally. I wish every pack came to me with mere voltage depression. That's easy to fix. It's very, very rare that I see any type of voltage depression in Honda packs... when Richard's pack came back to me it was at very low SoC, which matches the description of "not driving enough"...

The yellow stick with only like ~750mAh would have been the IMA light trigger here...
What's the discharge rate for the discharges in that graph? Those sticks looks seriously voltage depressed to me. They all start at ~7.2V and all of the discharge takes place below that. Good sticks won't hit below about 7.2 volts until near the end of discharge, at least at a 6.5 amp discharge rate, probably up to about 20 amps...

Here's a couple graphs of sticks discharged from about 50% SoC (at 6.5A). These aren't even in top form, but look how the cell-pair voltages stay above 2.4V until near the end. This is something I didn't catch on to until not too long ago - just how high voltage should stay until nearly empty. Basically, even up to pretty high discharge rates, voltage should remain lofty, in general above 1.25V per cell with adjustments for progressively higher rates, due to resistance... If they don't I call that "voltage depression." Maybe we have different definitions...

85907
 

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Discussion Starter #6
Eli and all, thanks for the input.

I have been grid charging (Prolong) about every 3 months for 24 to 30 hours. With colder temps I was able to get it to 178 volts, with the warmer weather I have not got it past 174. I might try again this weekend

One strange thing I have noticed after my JDM ECU Install for LB. Occasionally I will get strange SOC readings with OBDII. I will be cruising along with a voltage in the 150’s or so and the OBDII SOC reading will drop to 25% like a negative recall but voltage doesn’t drop and the SOC gauge on car won’t drop. It will go into background charging mode and I will reset SOC with OBDII. This has occurred less after I began to manage my assist more judiciously. I don’t use assist for acceleration as much as I do to maintain speed and lean burn on hills. Again this drains the battery very quickly. The first 10 miles or so of my commute is freeway with several small rolling hills. I use assist of 15 amps and Regen at 10 amps and am barely able to keep the SOC above 68% with IMAC&C.

I am going to drive it like I stole it for the next week. Use no 12v accessories and pay attention to the OBDII readings. I have never seen the voltage go above 174 with regen. I’ll try to push the limits to see what readings I can get.

I have the floor vents modded to pump air to the IPU and always have the fan on. This heats the battery to 70 in the winter and keeps it below 100 in the summer.

In regards to 12V accessories, I run a subwoofer with amp, all lights are LED. I usually run with parking lights on at all times for increased visibility. The county road for the last 20 miles of my commute has lots of areas with cross traffic and crazy yahoos trying to go 70 in a single lane 55 zone.

I sure would like to see what a healthy pack performs like. I’m leaning towards purchasing a new pack even though I have had any codes thrown.
 

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What's the discharge rate for the discharges in that graph? Those sticks looks seriously voltage depressed to me. They all start at ~7.2V and all of the discharge takes place below that. Good sticks won't hit below about 7.2 volts until near the end of discharge, at least at a 6.5 amp discharge rate, probably up to about 20 amps...

Here's a couple graphs of sticks discharged from about 50% SoC (at 6.5A). These aren't even in top form, but look how the cell-pair voltages stay above 2.4V until near the end. This is something I didn't catch on to until not too long ago - just how high voltage should stay until nearly empty. Basically, even up to pretty high discharge rates, voltage should remain lofty, in general above 1.25V per cell with adjustments for progressively higher rates, due to resistance... If they don't I call that "voltage depression." Maybe we have different definitions...
They're discharged at 18.6A.

Hmmmmm. I see what you're getting at here, but I promise there is no voltage depression in his sticks. They're just at low SoC, having literally never been charged to full in 2.5 years. Not sure how to prove it though? Your graphs would look much different if you only charged the sticks to 1500mAh and then discharged them, especially repeatedly.

Voltage depression, IMO, is not a problem in the Honda world. It's undesirable, but it never causes a pack to fail in the strict sense - it's basically 100% reversible, about 90% with a single cycle. When it does cause a pack to "fail", some slight programming changes fix it. That's why they were able to make the first wave of P0A7F(P1449)'s fixable with a flash in the 2nd generation Insight.... This doesn't quite hold true for the Toyota world, but maybe we should start another thread if we want to dive deep into this.

It is possible that we have different things in mind when using the term. Not sure. If those were 2nd generation Insight sticks, I would agree. It's amazing how much the use context matters......

Edit: Here's some classic voltage depression action on a 2nd generation Insight pack. These are stick pairs, so voltage is double a stick.

Before:

85908



After 1 cycle:

85909



Like magic. ;)
 

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hi.
new member here
i just put a 3 year full Warranty big amp in my insight (Bumblebee) with no experience, there self help was dead on. I just fell in love with the staff.
Sent them picture of my raccoon and they sent me pictures of the office cat.
I can not imagine this company doing a damn thing to hurt me.
no matter what the battery issues may become someday.
 

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Eli and all, thanks for the input.

I have been grid charging (Prolong) about every 3 months for 24 to 30 hours. With colder temps I was able to get it to 178 volts, with the warmer weather I have not got it past 174. I might try again this weekend
That seems reasonable.


One strange thing I have noticed after my JDM ECU Install for LB. Occasionally I will get strange SOC readings with OBDII. I will be cruising along with a voltage in the 150’s or so and the OBDII SOC reading will drop to 25% like a negative recall but voltage doesn’t drop and the SOC gauge on car won’t drop. It will go into background charging mode and I will reset SOC with OBDII. This has occurred less after I began to manage my assist more judiciously.

Hmm. That's a negative recal, regardless of what is going on with voltage or the dash cluster. Not a good sign. You should be able to use the battery down to 28% SoC and recharge it back up to 72% SoC in a smooth fashion.

I don’t use assist for acceleration as much as I do to maintain speed and lean burn on hills. Again this drains the battery very quickly. The first 10 miles or so of my commute is freeway with several small rolling hills. I use assist of 15 amps and Regen at 10 amps and am barely able to keep the SOC above 68% with IMAC&C.
This type of thing makes battery builders nervous. ;) With any battery and a device like IMAC&C, you are free to get excellent fuel economy... Until you use your battery up. Then you must put it back. Imagine if you go for a drive with your new battery and get 120MPG, but park for a weekend with your battery basically dead.. You pat yourself on the back, but is this really a good thing? My perspective has changed a lot in that sense, I cannot help but "drive for the battery" these days, even if it lowers my fuel economy. Not saying everyone should do that, but some kind of balance would be good.

So there are two hang points with the Insight programming, 28% on the discharge side and 72% on the charge side. When you're draining the battery, it will hang at 28.0% SoC on the OBDII Gauge until the battery is "actually" empty. Likewise, during charge SoC will hang at 72.0% until the battery is "actually" full. If your battery is healthy enough to make it down to 28% and you continue draining, you must then use the 72% hang to replace it, or you will hurt the battery long term. I'm afraid this rarely happens in the real world, without some kind of conscious effort, because automatic background charge stops at 70.1%. So that's one way low SoC can begin.....

I sure would like to see what a healthy pack performs like. I’m leaning towards purchasing a new pack even though I have had any codes thrown.
Suspect you would enjoy it a lot. Being able to tap the capacity is nice, as long as you're mindful that you have to put it back. ;)
 

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Discussion Starter #10
Yeah I’m definitely getting Negative recalls. No IMA Light yet. I’m going to discontinue use of IMAC&C to see what the battery does with its own cycles.

I think this battery is on its way out.

With a new pack would IMAC&C use be ok if I watched the SOC and didn’t drain it below around 60%. When I use it for assist on low grade rolling hills to maintain LB it’s at 15amp and for no more than a minute or so at a time.

What’s a good balance in your opinion? I try to keep LB at 55 mph going up hills, I’m not using it on flat lands trying to turn it into a PEHV.

I’m fairly certain you will be sending a new pack out to me. I just want to make sure my expectations are reasonable and I use it in a way that not going to kill it within 3 years.
 

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Discussion Starter #11
One more question. What’s your opinion of doing a pack top off nightly with a grid charger? Say it’s at 155 volts when I get home from work. Any benefit or damage to be done from grid charging to 169 volts and resetting OBDII to full which usually settles out at 74%?
 

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I don't understand being able to drive above 50% SOC. I drove my car from 2010 to 2018 and always seemed to be around 42%. Now that I have a BumbleBee (though in a different car without even a Calpod switch) I still seem to be in the lower half most of the time. Is there a thread anywhere that explains what I'm missing? Anyone in Portland want to drive my car and see what it does for you?

BTW, I trust Eli and BumbleBee and don't want to drive an Insight without a battery. It is such a great car. To me, the driving experience makes the battery mandatory, though I don't think this car runs as well as it should. I hope to be driving my old car soon (I've been saying that for a year.)
 

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Sure, I mean IMAC&C and MIMA type things are fine. We trust that you're not out to destroy the battery on purpose and would like at least a little life out of it. ;) Definitely recommend the 5 year warranty though.

It's hard to articulate, but since it's easier to use the battery up than it is to recharge it, the emphasis is on regen, regen, regen.... at every opportunity, as much as possible. With MIMA, it's easy to dial up 30-50A of regen everytime you come to a stop, on every moderate downhill, etc. I'm not sure how easy that is with IMAC&C.

There are basically two things that determine pack life. Cycles, and self-discharge difference between sticks. Which one is dominant depends on usage pattern. If you don't drive at all, self-discharge is dominant and you can expect around 2 years out of all but the most exceptionally well balanced packs. If you have a drive cycle that fully discharges and recharges the pack once per day, 7 days a week, you can expect about 2 years out of a pack; self discharge difference doesn't matter(within reason).

These packs(aftermarket and OEM) are only rated for around 800 full 100% cycles(That's a real number).. while you might get 10,000 5% cycles(I just made that up). The point is the more SoC you use with each cycle, the more you better use them wisely. There is nothing you can do about cycle damage.

A key to pack longevity then is that self-discharge difference can be overcome through driving habits and conditions. So if your battery:

1) has reasonable SD numbers and
2) you only ever use a few percent of the battery and
3) you maintain it at a high SoC so that regen helps overcome any SD differences there are,

That's when you get 15-20 year lifespans.

One of the things that marked the "golden age" of NiMH batteries (~2001-2009) was the exceptional self-discharge aging; it was very even. The "reasonable" SD numbers must be maintained over great amounts of time, ideally. That's the hardest part about building these batteries, at least if you care about longevity.

So the answer to your charging question depends more on the depth of discharge before recharging than it does the peak voltage you recharge to, though that matters too. It's a tough question to answer. In general, I've always frowned upon PHEV use on the little nickel packs, but if done properly you could minimize any damage. Articulating "properly" is the hard part.......
 

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I don't understand being able to drive above 50% SOC. I drove my car from 2010 to 2018 and always seemed to be around 42%. Now that I have a BumbleBee (though in a different car without even a Calpod switch) I still seem to be in the lower half most of the time. Is there a thread anywhere that explains what I'm missing? Anyone in Portland want to drive my car and see what it does for you?
Where the SoC gauge lives is a function of car condition, driving habits, driving conditions and probably others. I can maintain just about any Insight's battery at 70-80% SoC, but the worse the car's condition and the more demanding the driving conditions, the lower the fuel economy will be while doing so....
 
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Discussion Starter #15
So to summarize gas is way cheaper than NIMH batteries are. Don’t use your NIMH battery to augment mpg gains, that’s not there intended design function.

Good to know the 800 cycle number. That really puts things into perspective.
I do believe A replacement battery from you is in my near future. I got off on a poor start with my current battery.

I promise to drive it for longevity and not for MPG gains with the knowledge acquired here.

Thanks for your input Eli, I have a bit of a better understanding how the Battery works now.
 

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Not explicitly at least. With a stock Insight, it's OK to just let the car do it's thing, overall. With something like MIMA or IMAC&C, I would say it's OK to increase utilization a bit, as long as you match it with a corresponding increase in regen, which is easy to do.

I do have plenty of anecdotal evidence that "0-50% SoC" people's batteries don't last as long as "50-100% SoC" people. I don't really know how to advise the 0-50% people, they often seem to feel helpless to make it change, which is possible. In those cases it's usually due to a critically underpowered engine, sometimes combined with other things like the wrong tires. It's really difficult to keep off the IMA battery in those cases. Wrong tires are double edged because they increase IMA battery use on acceleration and decrease available regen on coasting.

Regen is very dependent on driving style, in multiple ways. I've seen plenty of Insight owners who are in the habit of clutching in as soon as you need to start slowing down with the physical brakes. The opposite of that is regen-centric anticipation. The more anticipation you are able to produce in your driving, the better. If I'm traveling along at 55mph and a light turns red a good distance in front of me, I will downshift through all the gears all the way to 2nd, soaking up as much as I can. If it's only a short distance, I will go straight to 2nd. The goal in each of these cases is to increase the time before you have to actually stop. I understand you have a CVT, but you can still implement anticipation. It tends to result in improved fuel economy in general.

Of course, it doesn't work very well in heavy traffic; everyone just fills your gaps......
 
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Discussion Starter #17
I Regen as much as possible. Try to use the brakes to come to a stop from 15 mph or less. With anticipation and IMAC&C this is easy and all helps with MPG.

What can you say about the negative affects of heat on the battery? I have so far been able to keep it under 100. When does heat become an issue?

I’m looking forward to seeing what this new battery will do for my LB CVT. Honestly I feel like throwing in towel and calling it quits on my current battery. I’m sure an IMA light is just around the corner.

Thanks again for the input. I feel I small bit more knowledge about your batteries and how to manage their lifecycle
 

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Discussion Starter #18
Also when using IMAC&C for Regen is there an amp range to stay under. I’m worry about hitting it with more than 30-40 amps for more than a few seconds. I try to mimic patterns I see the car naturally doing.
 

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They're discharged at 18.6A.
Thanks... That would make some difference, about -0.073V, so my 2.4V at 6.5A would be about 2.33V were it an 18.6A discharge.

I promise there is no voltage depression in his sticks. They're just at low SoC, having literally never been charged to full in 2.5 years. Not sure how to prove it though? Your graphs would look much different if you only charged the sticks to 1500mAh and then discharged them, especially repeatedly.
I only charged these sticks to ~3400mAh and then did those discharges. I had done charges to about 1500 before and saw no difference. I've been using my in-car pack between zero and about 10-30% SoC for ages (so max of about 2000mAh charged) and have only seen the voltage increase at lower charge states, though sounds like you're suggesting that it'd slump, sag... I would see saggage - if I charged up to ~75% and then came back down. The only way I can avoid saggage at low charge state is to use low charge state. Even one cycle up will result in saggage down low. Part of that I think is because I have old cells with less than new capacity...

Basically, whatever Richard's sticks have/had - call it voltage depression or 'crud' and 'high IR', etc. - those voltages should have been higher. The inflection point (where the curves start to flatten-out after start of discharge) for instance is about 6.9V - so 1.15V per cell. If you go back to my graphs and look for the voltage at about +1500 or so, it's about 2.52V for a cell-pair, subtract 0.07 to adjust for your higher discharge rate, and the comparable voltage is 2.45V, or 1.225V per cell. On a pack level that'd be 120 X 1.15V=138V vs. 120 X 1.225V=147V... That 138V is nearing assist-throttling territory... Actually, the lowest curve hits 6.6V after only about -250mAh discharge, so that's about how much unmolested usable capacity Richard would've been getting out of these sticks...

^This stuff applies to your following comment, too. Whatever we call it, sagging voltages such as those in your first graph might not cause a pack to fail out-right, but it definitely stunts performance, and I suspect it has compounding effects over time that at least lead to failure:

Voltage depression, IMO, is not a problem in the Honda world. It's undesirable, but it never causes a pack to fail in the strict sense - it's basically 100% reversible, about 90% with a single cycle...
It is possible that we have different things in mind when using the term. Not sure.
Probably. I use the term loosely ("voltage depression"). Any voltage sagging is 'voltage depression' to me. I don't know how to differentiate between, say, 'high IR' - which accompanies voltage depression, or just 'voltage depression/memory effect' in isolation, or what have you. I've seen just 'high IR' cells, without being VD, but I don't think I've ever seen VD cells without higher than normal IR.
 

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Edit: Here's some classic voltage depression action on a 2nd generation Insight pack. These are stick pairs, so voltage is double a stick.
Before:After 1 cycle:Like magic. ;)
I've never worked with 2nd gen cells before... But, first, what's the discharge rate here? If we compare my graphs to even the second one, which you say isn't voltage depressed, we see that my voltage/s still are much higher at comparable points. Mine doesn't hit 2.4V per cell pair (14.4V were it a stick-pair) until there's only about 400mAh of capacity left. If we find that point in your 2nd graph (about -5500mAh), we see that the voltage is only about 13.4V, so 1V lower than mine...

What do we call that? Surely higher voltage is better, right?

Here's the thing: As I mentioned above, my voltages would sag, maybe/probably as much as yours in the 2nd graph - if I charged to full and then did a discharge. I've imagined that new, newer cells wouldn't sag like that, but maybe I'm wrong. Maybe it's a phenomenon common to all NiMH??

My theory is that 'degradation' is a function of whatever this phenomenon is, whatever causes voltages to sag when you charge high and then try to use low charge state. It's like 'stuff' ends up shifting to one charge state range or the other - it can't be in both places at once... When you charge high stuff shifts high - and then it's not available low; when you stay low stuff stays low. The clincher in this theory, though, is that charging is the more burdensome process for Insight NiMH cells (ex. heat up more), for whatever reason, so charging when at high SoC causes more degradation than charging when at low SoC... Plus, discharging to below some voltage level, like 1.1V, also has a palliative/rejuvenating impact. As I mentioned earlier, I don't know if these are actually two processes or simply one, or rather, like 2 sides of the same process...

Anyway, sorry all for cluttering-up the thread. I debated whether I should post anything at all, as these types of discussions generally don't go anywhere these days. But it's all stuff that I've been thinking hard about, somewhat testing, for a long time now. I just had to get it off my chest. Eli's about the only one around here who might be able to...shed light on the ideas. So, I just can't resist unloading...
 
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