1.6V NiZn complements 1.6V lithium primary AAs

[Paul_in_Maryland]

I'm amazed how few CPFers have embraced PowerGenix nickel-zinc (NiZn) AA cells. Nickel-metal-hydride (NiMH) AAs were popular, in part, because they delivered a voltage under load that was similar to that of alkalines. Now that L91 lithium AAs have become our favorite AA primary cell, doesn't it make sense to interchange them with a rechargeable AA that is better-matched? Lithium and NiZn share the same voltage under load, the same high performance in low temperatures, and similar resistance. Why not cut ties with 1.2V to 1.5V legacy chemistries and enjoy the new standard voltage: 1.6V?

 

[lctorana]

Never seen them for sale anywhere, either online or B&M.

They seem to exist only in CPF discussions.

 

[lemlux]

Paul: As you know, I use Ni-Zn cells.

I appreciatively use them in simple 1aa, 2aa, and 3aa configurations.

My major concern is that I remain ignorant of any safe way to charge these puppies in a serial pack. This is a particular concern with my 6AA widebody fivemega bodies and 6aa 6S, 12aa 6S2P, and 18 aa 9s2P battery holders which are a PITA to dissassemble and reassemble. Its a lesser, but real concern with my 4aa to D and 8aa to 2D battery holders.

 

[peskyphotons]

I am very interested these new batteries and have been trying to find out more about them. I emailed Powergenix asking about the characteristics of the cells, can they take being over discharged or left in the charger etc and received no response at all. I called ZTS (several months ago) to find out if there is a tester available and at that time is was at best a while off. It would be nice to know how these cells like to be treated. Being able to test my eneloops has been very useful and I would like to be able to test the NiZn cells also.

Thanks,
Alex

 

[Mr Happy]

There have been at least two threads with active discussions of the NiZn cells around here. By reading those threads it is possible to learn everything there is to know about the characteristics of those cells, how to charge them, what happens if you mistreat them, etc.

The short summary is that they are nice cells with a high power output, but they are potentially fragile with a shorter expected life than eneloops and easily damaged by over discharge and other kinds of mistreatment. You can discharge (but not charge) them in a C9000 for test purposes, and you may be able to charge series packs if you are careful (there is incomplete testing on this).

These cells have a niche, but they don't quite appear to be ready to replace NiMH cells in every application.

 

[45/70]

My original intent for NiZn was, as you suggest, a replacement/substitute for lithium AA's, that is more versatile. For that purpose they seem to be working out well.

As for them replacing my LSD NiMH cells, I don't really see that happening anytime soon, unless there is a significant improvement in the NiZn chemistry. Admittedly my uses are not particularly high current applications, but so far, in devices that don't require the higher voltage that the NiZn's provide, my eneloops still demonstrate superior performance, overall. Add to that their inconsistency from cell to cell and their considerably shorter expected cycle life, I don't see them as viable replacement for LSD NiMH's......yet.

Dave

 

[MarioJP]

I would have to agree with Mr.Happy.

Bottom line,unless your device requires the extra voltage to operate properly I would stick with eneloops for devices that are sensitive to low voltage as these cells have balancing issues,and are quite fragile. you gain no benefit for devices that works well below 1.5v.

Take for instance, my USB mobile booster charger to charge mobile devices that requires 5v.

The only difference in this scenario using Nizn cells in these booster devices is that it cut the draw current by half (for a short period anyways).

Furthermore, I also did couple of tests on different mobile devices using nizn,and eneloops as a comparison.

For low power drain mobile devices such as Iphone 3g or Ipod Nano. Not only was I able to fully charge these devices using eneloops they still had charge left over for another round. Did the same comparison test with Nizn. It seems that they last shorter on the second round than the eneloops or close to being the same charge time.

Difference?? While doing this tests my nizn cells are croaking, that in fact has gotten to the point where they are unreliable to be used on high drain devices but still perfect for my electric toothbrush and my wireless gamepad, while the eneloops continues to shine. And another thing. Why do these cells get too dam hot too fast? even while being discharged. It almost started to melt my mobile booster as it started to smell like plastic, burned my fingers just by trying to get them out lol.

So your right mr.happy these are definitely "niche" cells and I don't see them replacing NiMh anytime soon, but def can be alternative to those Lithium primaries that can be quite an expense to keep energizer not only happy that you are using their cells but also keeping their pockets well fed:devil::devil:

 

[Lynx_Arc]

The only devices I would consider nizn cells for would be my indoor outdoor thermometer and caller id displays which eat batteries and don't run half as long off nimh lsd cells due to their voltage sensitivity. The problem I have seen is they haven't been out long enough to know what self discharge they are capable of after 6 months to a year for those devices and I am unwilling to invest in them when I could spend money on primaries that I know would work for the next 5 years instead. Also I am concerned the 1.9v could kill some devices when more than one cell is used the overvoltage can reach that of having extra batteries.

 

[Paul_in_Maryland]

In response to the legitimate comments about longterim standby power, let me clarify. I agree that NiZn can't replace NiZn LSDs. But L91 lithiums can. In most cases, you'll be using the standby cells maybe one event a year. Use NiZn for everyday use; use lithium primaries for standby/emergencies. I keep NiZs AAs in my keyring 1xAA lights. But inside my keyring's spare AA holder is a lithium AA.

The point is, for some of us, our aversion to "paying by the minute" has prevented us from appreciating lithium primaries in a niche role. I figure that using lithium primary cells in my backup lights will cost me no more than $15 a year.

 

[MichaelW]

Plus more voltage kind of goes against the Vf trend of LEDs.

The new Rebel ES (not old Rebel es), has a Vf of 3.25 volts at 1.5 amps.

So, are two cell flashlights going to move from boost to buck circuits?

 

[alpg88]

The point is, for some of us, our aversion to "paying by the minute" has prevented us from appreciating lithium primaries in a niche role. I figure that using lithium primary cells in my backup lights will cost me no more than $15 a year.

i don't know where you get your data, but ppl do use litmus AA. i do it for 10 years at least, many ppl i know use them too, so are members here.
we are all aware of their voltage, extreme temp. performance, ans 2x capacity compared to nizh.
not sure what it is that you wanted to discuss in this thread.

 

[Paul_in_Maryland]

not sure what it is that you wanted to discuss in this thread.

Basically, this:
1. 1.2V rechargeable are voltage-matched to alkaline AAs, not to 1.6V lithium AAs.
2. Enthusiasts prefer 1.6V lithium AAs to alkaline AAs for daily and backup use.
3. Therefore, if one is already using lithium AAs for EDC or backup because of their higher voltage or improved performance in low temperatures, 1.6V NiZn makes a well-suited EDC complement.

 

[alpg88]

Why not cut ties with 1.2V to 1.5V legacy chemistries and enjoy the new standard voltage: 1.6V?

oh, i think i found what you wanted to talk about.

well, why cut?? nimh are more reliable, a lot more available, last longer, and some can easy pull 10 amps, 3x1.2= easy dd led
show me 1 nizh cell that can do that??
plus if you look at total energy delivered(v\ah) nizh offer as much as lower capacity nimh. nizn are 1.5 ah at most.
also show me 1 lsd nizh.

give me 1 good reason why I should go with exotic cells, that aren't even available other than the web.
instead of proven, readily available, reliable, nimh. that i can charge in series, with many type of chargers available, and also with cc cv power supply.

 

[Paul_in_Maryland]

oh, i think i found what you wanted to talk about.

well, why cut?? nimh are more reliable, a lot more available,

Are yo usaying NiZn are easier to find on the Web? Or in a walk-in store? If you mean on the Web, NiZn can be readily bought on Amazon or eBay. If you mean in a walk-in store, if I needed them right away, I'd be happy with lithiums. Besides, why is it so important to be able to buy one's rechargeable cells in a brick-and-mortar store? Should CPFers avoid lithium-ion cells because they can't buy replacements at the drugstore?

last longer,

In direct-drive, yes. But if a light is regulated, NiZn's higher voltage means that the regulator draws less current.

and some can easy pull 10 amps, 3x1.2= easy dd led
show me 1 nizh cell that can do that??

PowerGenix. That's why they're preferred and recommended by flash enthusiasts.

plus if you look at total energy delivered(v\ah) nizh offer as much as lower capacity nimh. nizn are 1.5 ah at most.

also show me 1 lsd nizh.

I don't have to: I never said that NiZn was a good choice for long-term storage. I recommended NiZn for everyday, lithium where the cell would sit idle for long periods.

give me 1 good reason why I should go with exotic cells, that aren't even available other than the web.
instead of proven, readily available, reliable, nimh. that i can charge in series, with many type of chargers available, and also with cc cv power supply.

Whether direct-drive or regulated, they'll make your Malkoff M31 about 30 percent brighter.

For a battery pack, then yes, your NiMH makes perfect sense.

Note that I'm not saying, "Nickel-zinc cells are the more sensible choice for everyone." But it sounds as though you're saying "Nickel-zinc cells are the more sensible choice for no one."

 

[alpg88]

Are yo usaying NiZn are easier to find on the Web? Or in a walk-in store? If you mean on the Web, NiZn can be readily bought on Amazon or eBay. If you mean in a walk-in store, if I needed them right away, I'd be happy with lithium's. Besides, why is it so important to be able to buy one's rechargeable cells in a brick-and-mortar store? Should CPFers avoid lithium-ion cells because they can't buy replacements at the drugstore?

yes no stores (almost) sell those, as for li ion, we are not talking about those, since your thread is not substituting li ion for something else.
but you got a point, i never seen eneloops in stores,(other than fake ones in china town, for $30 for 4 cells

In direct-drive, yes. But if a light is regulated, NiZn's higher voltage means that the regulator draws less current.

that also mean regulator will run hotter, wasting more v into heat.
in regulated light nizn doesn't offer any advantage.

PowerGenix. That's why they're preferred and recommended by flash enthusiasts.

that is not the answer, and please, don't chop my question apart, and answer parts it out of the contest.
my original question was.

nimh are more reliable, a lot more available, last longer (as in charging cycles, not shelf life), and some can easy pull 10 amps, 3x1.2= easy dd led
show me 1 nizh cell that can do that??

Whether direct-drive and regulated, they'll make your Malkoff M31 about 30 percent brighter.

that is just 1 instant, they wouldn't make any of mine regulated lights brighter, or last longer, (i tried powering them off different cells,) that would also burn my dd lights.

Note that I'm not saying, "Nickel-zinc cells are the more sensible choice for everyone." But it sounds as though you're saying "Nickel-zinc cells are the more sensible choice for no one

well for now i don't see them to give any advantage in lights that nimh (a better cell) can't provide.

for cameras, or flashguns, maybe, thou there were reports of them burning out flashes for few ppl, ( things that are made for 1,5v can be used with 1,2v or 1,6v cell as l91, but 1,9v might kill them), i came across that at photo forums, when i was reaching these cells, my research showed that there is no advantage at this time that nizn offer, in light application. they are just an exotic new cell chemistry, a novelty, just like bamboo, or exotic wood floor instead of hardwood floor.
also you might wanna read few threads here on nizh cells, how they behave in real world.

 

[MarioJP]

SO tell me why can't these nizn cells be charged in series like in a battery pack?. What seems to be the problem?

I also forgot to mention to why these cells became unreliable. Reason is they have develop a such of self discharge that actually surpassed the energizer's nimh infamous high rate of self discharge believe it or not.

But at least my 7 nimh energizers still works well in my battery pack for low drain application as I cycled them many times and have seen an improvement.

Anyways seems like these nizn cells has little bit of nimh characteristics when it comes to self discharge except much worst and gets to that state very quickly.

 

[Mr Happy]

SO tell me why can't these nizn cells be charged in series like in a battery pack?. What seems to be the problem?

NiZn cells can be charged in series, but it has to be done the same way as Li-ion with voltage balancing. There are no regular chargers available today with that capability so it remains out of reach.

NiMH cells can be charged in series without balancing because they have an "overflow" capability. If you charge a string of cells in series some of them will reach full charge before the others. When this happens to NiMH cells they can "overflow" the excess charge while the other cells catch up. NiZn cells have very little overflow capability so if you try the same thing with them you may damage the ones that get overcharged.

 

[MarioJP]

I am starting to think that these batteries reminds me of renewal reusable cells. very short lifespan.

I am thinking after 25-35 real world cycles these cells are finished. Definitely did no achieve 100 cycles. The problem with these cells is overtime these cells will start to act like the drawbacks of a primary lithium cell.

Just like a lithium cell will act like a current regulator except the actual current is not being limited but rather will force you to lower the current as these cells will get too hot where as when they were new this was not a problem.

This why I stop using these cells in my mobile booster charger, and also they die too quickly and 1 or 2 cells comes out severely drained ant that is starting to get annoying

 

[Paul_in_Maryland]

Sometimes, when I charge 2 or more at a time, they'll come out from the charger at different voltages; one will have reached 1.73V, while another never reached 1.6V. I now own two of the white "1 hour" chargers, and I wish I had four of them. I get the feeling that charging more than one at a time is a roll of the dice. But you can't buy the charger alone, and I already own about 22 of the cells.

 

[Mr Happy]

Sometimes, when I charge 2 or more at a time, they'll come out from the charger at different voltages; one will have reached 1.73V, while another never reached 1.6V. I now own two of the white "1 hour" chargers, and I wish I had four of them. I get the feeling that charging more than one at a time is a roll of the dice. But you can't buy the charger alone, and I already own about 22 of the cells.

The cell that doesn't reach 1.6 V is a failing cell. You should mark it to keep track of it and expect to remove it from general use. You should also try to note its history so that you get any clues as to why it failed.

The explanation for the observed behavior is that the 1 hour charger apparently tries to charge all the cells in parallel up to a target 1.9 V and terminates when the current reaches a low threshold. (The charger counts the number of cells inserted and adjusts the termination current accordingly.) If one of the cells is failing it will draw excess current from the charger, thus pulling down the voltage and preventing the other cells from reaching 1.9 V. The charger will also not reach the desired low current termination point and will end the charge on the backup timer or on over temperature.