Egsise
Banned
Quark AA has overdischarge protection at 0.9V, which is still safe for NiMH, you mean it is too low for NiZn?
NIZN VERSUS NIMH
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VidPro
Flashlight Enthusiast
if it is anything like the 2 mobile voltage boosting 5V usblike chargers i have:
They dont have enough operation voltage with alkalines very shortly
hold out "ok" with ni-mhys but still as the voltage droops cant keep the boost going well.
they thrive with the higher voltage of the lithium cells and will drain the lithiums almost completely (way to much cost).
The boost pulls down the battery voltages , then the boost curcuit begins to faulter , it will either sputter or just stop at that point, not doing any usefull charging.
WHEN those are the symptoms, the additional voltage will allow the curcuit to continue to operate, BUT is not going to have the boost curcuit run that much harder, as they are limited in total output.
most boost curcuits (even some really bad ones) will draw less current from the battery when the voltage is maintained higher.
So
if voltage holding was the issue, the higher voltage chemistry should maintain that better. the charge rate out of the device should not change much over the rate it was doing with good fresh cell items in it. So there shouldnt be some huge charge speed increase, just longer operation at full.
If your Cell charger always WORKS but just doesnt give you enough current EVER, then switch to a Direct drive 4xAA one, and use ni-mhy or even alky, they dont have to do a boost, they have enough total power in them, and with all the extra total power they can be stronger in their charge. Often they are pure simplicity and way higher efficency, but you wouldnt want to use it on something that cant cope with higher total power. Many (but not all) devices using USB charging work fine with the DD voltages that go from ~5.4-4.8v no bs, no lossey curcuit , no failing curcuit junk, no reverse charge of batts as it will cutoff when the voltage drops to low to act like a USB.
Stuffing Ni-Zinc into 4xAA with Direct drive, will raise the voltage to high, which could toast the USB input on the device. i have tested a few USB inputs on the li-ion charging stuff (pda, Phone, external li-ion solar thing) and they start to break around 7V, so i stay below 6V
When determining the "runtime" of the cell charger using a boost curcuit, you just do the Watts to Watts comparison of the battery, the ~2.5W of the battery capacity is then usefull figure. When voltage is higher the actual current drawn to get to the same watts is lower.
If the cell charger never has enough voltage for its cheezy curcuit thing in it, then having a higher voltage battery in there solves that issue, and the actual watt total of the battery is inconsequential, When, with the high voltage the thing actually Works, instead of sputtering and stopping.
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VidPro
Flashlight Enthusiast
think i finnaly fixed that post. remind me next time to read better :ironic:
What kind of 4XAA cell charger?
What kind of 4XAA cell charger?
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well it does work and I forgot to mentioned that this wasn't a problem with my previous phone. Its the newer phones with a faster processor,3G,wifi that I can't seem to top it off on a single charge.
But it does charges my phone to almost full like 75 to 80%. My other phone would not only be topped off but still have charge left over from the eneloops.
This phone however drains them completely and its not fully charged.
But it does charges my phone to almost full like 75 to 80%. My other phone would not only be topped off but still have charge left over from the eneloops.
This phone however drains them completely and its not fully charged.
VidPro
Flashlight Enthusiast
Well if it drains all the cells then it is doing something right, or something wrong 
what is the Max capacity of the devices internal battery? logically even a really efficient or DD cell charger will have quite a bit of losses in the phones internal charger thing. then if the charger has driver too, the losses could easily get to 50%
(because of that some devices we skipped the curcuits and just add the battery direct instead)
so how does the device act with the mere 500ma charge of one of them small wall wart switching chargers , or via a computer?
there is one device i know of , that uses 2 methods, one for anything it THINKS could be connected to a computer, wherin it MUST stay below 500ma to not ruin a computers USB port.
and when the data lines of the USB are Tied (specially) , a Specific Flag that the charge curcuit is trained to see, switches it into the faster charge. That device prefers to be charged with its own Data tied line charger (obviously)
plus there are some phone devices that actuall allow the charging curcuit to be rate changed, deep in the menu somewhere.
But what i really want to know is What is IN your 4XAA cell charger. i have one i made , and one i bought. the one i made is DD, the one i bought is also DD (batteries just direct connected plus cute led with diode to show it is on).
What kind of cord do you use to connect? I use some lightweight rollup (retract) cords, and they certannly slow down the max rate, because the small wire, but is sufficent.
and how far can i go off topic rambling , and making more errors
what is the Max capacity of the devices internal battery? logically even a really efficient or DD cell charger will have quite a bit of losses in the phones internal charger thing. then if the charger has driver too, the losses could easily get to 50%
(because of that some devices we skipped the curcuits and just add the battery direct instead)
so how does the device act with the mere 500ma charge of one of them small wall wart switching chargers , or via a computer?
there is one device i know of , that uses 2 methods, one for anything it THINKS could be connected to a computer, wherin it MUST stay below 500ma to not ruin a computers USB port.
and when the data lines of the USB are Tied (specially) , a Specific Flag that the charge curcuit is trained to see, switches it into the faster charge. That device prefers to be charged with its own Data tied line charger (obviously)
plus there are some phone devices that actuall allow the charging curcuit to be rate changed, deep in the menu somewhere.
But what i really want to know is What is IN your 4XAA cell charger. i have one i made , and one i bought. the one i made is DD, the one i bought is also DD (batteries just direct connected plus cute led with diode to show it is on).
What kind of cord do you use to connect? I use some lightweight rollup (retract) cords, and they certannly slow down the max rate, because the small wire, but is sufficent.
and how far can i go off topic rambling , and making more errors
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This charger is weird. You can use from 2 to 4 AA to start the charge. I can't tell if this charger has a independent booster circuit per pair or its wired in parallel per pair. Its definitely not a 4AA one circuit.
All i know is if you pull one AA out out of 4 the charger is still on charging the usb device. Does not matter which AA you pull out either. This is a very interesting charger.
On the data tech specs. It pushes 800ma from the usb port. This explains why my phone gets warm after 5 minutes and sometimes my phone gets around 40c. I know this because I have a battery app that monitors the temp. When the phone gets to 41c the charging stops until the phone cools down.
http://www.tekkeon.com/products-tekcharge1550.html
My phone's battery is a 1500mAh Lion Polymer.
All i know is if you pull one AA out out of 4 the charger is still on charging the usb device. Does not matter which AA you pull out either. This is a very interesting charger.
On the data tech specs. It pushes 800ma from the usb port. This explains why my phone gets warm after 5 minutes and sometimes my phone gets around 40c. I know this because I have a battery app that monitors the temp. When the phone gets to 41c the charging stops until the phone cools down.
http://www.tekkeon.com/products-tekcharge1550.html
My phone's battery is a 1500mAh Lion Polymer.
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VidPro
Flashlight Enthusiast
yup boost, so it wont go much faster or better.
so putting in Ni-Zi should work ok, the In voltage will still be below the out voltage, but it wont change rate much, depending on the boost curcuit it could increase effeciency slightly.
find the low end, to discover if it could drain them to far (being boost), how low does it drain cell items?
with that at least when using parellels the batts can maintain the current of the boosting better.
1500ma cell battery is not like your going to get 2x charges with it like they might with a cell that uses some 600-800ma battery.
i have some 800ma quoted boosters in some china ones, they arent 800ma, but i didnt test exact, as i would need a scope to see everything going on.
or just get a more simplistic 4xAA that is raw and direct, then dont put ni-z in that.
if its working , its better than some mabey best to enjoy that, vrses re-wiring it.
so putting in Ni-Zi should work ok, the In voltage will still be below the out voltage, but it wont change rate much, depending on the boost curcuit it could increase effeciency slightly.
find the low end, to discover if it could drain them to far (being boost), how low does it drain cell items?
with that at least when using parellels the batts can maintain the current of the boosting better.
1500ma cell battery is not like your going to get 2x charges with it like they might with a cell that uses some 600-800ma battery.
i have some 800ma quoted boosters in some china ones, they arent 800ma, but i didnt test exact, as i would need a scope to see everything going on.
or just get a more simplistic 4xAA that is raw and direct, then dont put ni-z in that.
if its working , its better than some
mabey best to enjoy that, vrses re-wiring it.
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yup boost, so it wont go much faster or better.
so putting in Ni-Zi should work ok, the In voltage will still be below the out voltage, but it wont change rate much, depending on the boost curcuit it could increase effeciency slightly. find the low end, to discover if it could drain them to far.
at least when using parellels the batts can maintain the current of the boosting better.
1500ma cell battery is not like your going to get 2x charges with it like they might with a cell that uses some 600-800ma battery.
i have some 800ma quoted boosters in some china ones, they arent 800ma, but i didnt test exact, as i would need a scope to see everything going on.
or just get a more simplistic 4xAA that is raw and direct, then dont put ni-z in that.
if its working , its better than some
Won't Ni-zn burn this charger out??. one time I bought energizer Lithium ultimate. The usb charger was making a buzzing pitching noise, or a low pitch sound when it was charging my phone. and the AA's were getting almost hot!. The whining pitch was louder when using 2 AA than using all 4. But no buzzing or low pitch noise when using NiMh cells 2 or 4. With that said I am not using lithium AA on this charger again lol.
and as for the eneloops cells. When batteries are drained I measure the voltage the moment i take them out.
all 4 of them read in my multimeter 0.90 idle voltage. if not lower sometimes 0.85V off the usb charger. I have to wait until the voltage recovers back to 1v before I i put them in the charger
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VidPro
Flashlight Enthusiast
did you load 4 lithium AA cells or 2 ?
if the thing is going to freak out over lithium, and it is not because the Energyser lithiums overcurrent kicked in, then it will freak over these.
the energyser lithiums will kick in overcurrent protection, when it does , the voltage of the lithium will drop, the booster will increase in current as the voltage drops, then the booster will squeal like a pig and , and then heat up, then the canoe turns over and the hillpeople will kill everyone i saw the movie
on the other hand the NIZN also break on very high currents.
try a Direct drive 4xAA cell charger with enloops, kicks butt no losses , no wastes, no curcuit junk, other than in the device your charging, no reverse charge, long live the batteries.
if the thing is going to freak out over lithium, and it is not because the Energyser lithiums overcurrent kicked in, then it will freak over these.
the energyser lithiums will kick in overcurrent protection, when it does , the voltage of the lithium will drop, the booster will increase in current as the voltage drops, then the booster will squeal like a pig and , and then heat up, then the canoe turns over and the hillpeople will kill everyone
i saw the movieon the other hand the NIZN also break on very high currents.
try a Direct drive 4xAA cell charger with enloops, kicks butt no losses , no wastes, no curcuit junk, other than in the device your charging, no reverse charge, long live the batteries.
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VidPro
Flashlight Enthusiast
well it sounds like it has some efficency issues. dont they all.
these devices are not often sold as being permenent chargers, and charge WHILE operating type of things, more like get you by for a while, till you get to a real power source.
that is why i go with adding on battery, extended battery, solar , and all the other methods of surviving without a power cord.
note the word "Emergency" often utalised.
these devices are not often sold as being permenent chargers, and charge WHILE operating type of things, more like get you by for a while, till you get to a real power source.
that is why i go with adding on battery, extended battery, solar , and all the other methods of surviving without a power cord.
note the word "Emergency" often utalised.
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I did not use the lithium cells too long. Just seems this charger is meant for nimh cells. No pitching and does not heat up with 4 of them. so Higher voltage is bad??
with the nimh cells that are rated 2000mah it does charge my phone from 10 to 75-80% on a single charge. Not bad though I guess what i can do is turn off most of the phone services when its charging to maximize the charge. like dim the display shorten the time for the display to turn off.
with the nimh cells that are rated 2000mah it does charge my phone from 10 to 75-80% on a single charge. Not bad though I guess what i can do is turn off most of the phone services when its charging to maximize the charge. like dim the display shorten the time for the display to turn off.
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VidPro
Flashlight Enthusiast
Your testing showed that higher voltage lithium was bad news, they are higher voltage just like the zinc.
You were certannly smart for stopping a bad situation, from getting worse, but it works on 3v , it has a driver, it outputs 5v , it has to be a boost , , , hmm mabey it was one of those really loose boosters, like a voltage doubler curcuit. as the voltage input changes so too does the output voltage, and the total current.
could find out how it acts quick enough, either using a adjustable power supply, or just doing I/O readings on both sides of it.
approx guesses: (including probable realities)
4x2000ma batteries ~9 watts
the phone is sucking ~1W/h while on
~4 W/h output out of charger on a good day
~1.5 W/h watts lost via both charge curcuits
2 hour charge time with use
~4.5W li-ion battery
that is completly par.
battery dead even though it has the "watts" to almost charge 2 times,
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the only readings i am able to do is when using 2 cells. I measured the current as the charger was charging. boy does it draw quite a current almost 2A! lol. No wonder the spring contacts gets hot!. Don't think Lithium AA cells would appreciate that kind of current draw, especially if its constant current. At that rate and if I walked away. The AA Lithium cells would get too hot and possibly start melting the plastic lol.
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Ray_of_Light
Flashlight Enthusiast
For series charging of Ni-Zn AA batteries, use CV method, 1 A limited, 1.9 V per cell, and terminate the charge when the current drops below 90 mA.
You need a thermal stop if the temperature of any battery in the pack raises of 15 C over ambient temperature, or 40 C absolute temperature.
If you want the 200 full cycles from a pack of Ni-Zn, you need charge balancing and temperature compensation, otherwise with a simple series charging at 1,9 V /cell, you may end up with 20-30 cycles. Unlike Ni-CD and Ni-Mh, you can't use slow charging to equalise the cells charge unbalance, because they will leak.
To keep the pack alive, you need to recharge every month, or everytime the open circuit voltage of any of the cells fall below 1.68 V.
Hope this helps
Anthony
You need a thermal stop if the temperature of any battery in the pack raises of 15 C over ambient temperature, or 40 C absolute temperature.
If you want the 200 full cycles from a pack of Ni-Zn, you need charge balancing and temperature compensation, otherwise with a simple series charging at 1,9 V /cell, you may end up with 20-30 cycles. Unlike Ni-CD and Ni-Mh, you can't use slow charging to equalise the cells charge unbalance, because they will leak.
To keep the pack alive, you need to recharge every month, or everytime the open circuit voltage of any of the cells fall below 1.68 V.
Hope this helps
Anthony
Thanks for the suggestion Anthony, but can you explain where you got that information from? I thought on the website (at least one of them for NiZn) it called for CC until a certain point, then CV until the end of charging. I have been told this is how Li-Po and Li-Ions are currently charged, except the voltages are at different levels than NiZn, obviously.
core
Newly Enlightened
The PowerGenix spec sheet does in fact call for a two step procedure:
- Constant Current: From C/2 to C to 1.9V per cell
- Constant Voltage: 1.9V/cell until current < 75mA
But that is not in series, which I think is the key here.
- Constant Current: From C/2 to C to 1.9V per cell
- Constant Voltage: 1.9V/cell until current < 75mA
But that is not in series, which I think is the key here.
Ray_of_Light
Flashlight Enthusiast
Nickel-Zinc is a very old and well known battery chemistry, so is their charging parameters. Before Powergenix batteries, Nickel-Zinc chemistry never made to the mass market because of their very limited number of cycles, caused from some unappropriate properties of the zinc.
The problem I see with Powergenix battery is that, unlike Ni-CD and Ni-MH, there is no mechanism to recombine hydrogen and oxygen which produces at end of charge.
This is the reason why the battery cannot be overcharged or trickle charged, and charge has to be terminated when the idle currrent falls below 90 mA, and the series packs needs charge balancing. Overcharge will cause a leakage.
EDIT: * CV Method with 1 A current limit * is "about" the same to say CC at 1 A, then CV at 1.9 V till 90 mA idle. Pure CC+CV rely on a voltage comparator to switch source impedance at 1.9 V, while current-limited CV act as CC until the cell try to draw more than 1 A.
The first method is the one suggested from manufacturer for single cell charging, but is not suggested for series packs unless you closely monitor each cell with a balancer.
Anthony
The problem I see with Powergenix battery is that, unlike Ni-CD and Ni-MH, there is no mechanism to recombine hydrogen and oxygen which produces at end of charge.
This is the reason why the battery cannot be overcharged or trickle charged, and charge has to be terminated when the idle currrent falls below 90 mA, and the series packs needs charge balancing. Overcharge will cause a leakage.
EDIT: * CV Method with 1 A current limit * is "about" the same to say CC at 1 A, then CV at 1.9 V till 90 mA idle. Pure CC+CV rely on a voltage comparator to switch source impedance at 1.9 V, while current-limited CV act as CC until the cell try to draw more than 1 A.
The first method is the one suggested from manufacturer for single cell charging, but is not suggested for series packs unless you closely monitor each cell with a balancer.
Anthony
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