Excessive voltage from new Lithium AA battery cells.

[audioguru]

I have many solar garden lights. Most come with a very cheap old-fashioned Ni-Cad cell that rusts away in a couple of months. The latest ones have a 200mAh AAA size Ni-Cad that weighs almost nothing and it powers a garden light for only 3 hours after being charged in the sun all day.
Some came with a 350mAh AA size Ni-Cad cell but most were 600mAh. I replace the AA size Ni-Cads with Energizer 2300mAh Ni-MH cells.

 

[KeepItSimpleStupid]

The charge rates are 200, 300. 500 700 mA, 1, 1.5 and 2 A; No voltage because it does the delta(I,V) charge termination. Modes are charge, discharge, quick test, charge refresh.

==

NiCd-s are in the cordless phones; Li-ion in the GPS and Cell. I have an external charger I can use for them. I can carry an extra Li-ion for the cell and I can charge in one car with the engine off and the other car with the engine on, In my previous vehicle, I put a lighter socket in the trunk so I could charge a laptop, I have a couple of iGo chargers that have dual 120/12 VDC inputs. For giggles, I have a cheap 100 W inverter, but the new laptop bricks aren't happy using it. The inverter tends to shut off.

I also have external battery chargers for the laptops. I have a self contained chargeable 12 V SLA power source but I haven't used it in years.

The drill is a NiCd pack. I don;t use the drill much, but the two packs do OK. Two packs are the way to go.

I had hair trimmers that I think use Ni-cds. One is really tough to replace so I didn;t when it died. Dunno about the other one. One was Remington and the other Norelco, I have an old National Semiconductor LED RPN calculator that uses Nicds (soldered in), This year I replaced 4 Ni-cd packs in the phones. One lasted 8 years, but usauslly get 4 to 5 years out of them.

oral-b (toothbrush) has a special take-apart disposal mode, Not successful putting them back together, I have no idea about a Phillips Airfloss. Both basically sealed against water.

Two UPS's have SLA batteries. The Trip-lite doesn't even work in non-UPS mode with the batteries dead. Not sure about the APC. One was free (dead battery) and the other was like ($10) at a thrift store. So, it takes a $20 battery, VA rating is something like 500 W.

For giggles, since we are on power sources, I made a up a box using a Chinese step-down converter with V and I meters that uses a 5.5/2.1 or 5.5/2.5 inputs (I can switch polarity internally if required) and it uses an adapt-a-plug for output. If an adapter fries for a "critical" piece of equipment (typically network stuff), I can make a replacement usually with a 12 V adapter. I do have two network gizmos that aren't in service yet that use like 19 V.

At some point, I want to make a low voltage UPS using this platform. https://www.mini-box.com/OpenUPS I haven't selected a battery yet. I want to use at least four of the the Chinese step down converters and probably a Li-Po battery. I basically want a slim form factor to hide behind a piece of furniture close to the wall mostly to power a WIFI repeater. I want to do something with the plugs, but not sure what yet to prevent the wrong voltage out with over current protection. Internally it will be 24V wit 4 step down converters.

So,I want some sort of (box with a plug) that attaches to my LOW voltage UPS with say pots to select an overvoltage and current and polarity, if it's not in range, there will be no output. I could even put the programming resistors in the "box" which isn't a bad idea, but I still need an overcurrent shutdown to protect against an adapt-a-plug being reversed.

I finally tidied up my network stuff which is a "bunch of wallwarts" and put them on a shelf with two octopus cords in the rafters. I have no intermittents anymore. US plugs suck when it comes to wall warts. The European sockets seem to be much better being recessed.

 

[MrAl]

I have many solar garden lights. Most come with a very cheap old-fashioned Ni-Cad cell that rusts away in a couple of months. The latest ones have a 200mAh AAA size Ni-Cad that weighs almost nothing and it powers a garden light for only 3 hours after being charged in the sun all day.
Some came with a 350mAh AA size Ni-Cad cell but most were 600mAh. I replace the AA size Ni-Cads with Energizer 2300mAh Ni-MH cells.

So now you get 1/2 hour of light instead of 3 hours

Did the 2300's help much?

 

[MrAl]

The charge rates are 200, 300. 500 700 mA, 1, 1.5 and 2 A; No voltage because it does the delta(I,V) charge termination. Modes are charge, discharge, quick test, charge refresh.

==

NiCd-s are in the cordless phones; Li-ion in the GPS and Cell. I have an external charger I can use for them. I can carry an extra Li-ion for the cell and I can charge in one car with the engine off and the other car with the engine on, In my previous vehicle, I put a lighter socket in the trunk so I could charge a laptop, I have a couple of iGo chargers that have dual 120/12 VDC inputs. For giggles, I have a cheap 100 W inverter, but the new laptop bricks aren't happy using it. The inverter tends to shut off.

I also have external battery chargers for the laptops. I have a self contained chargeable 12 V SLA power source but I haven't used it in years.

The drill is a NiCd pack. I don;t use the drill much, but the two packs do OK. Two packs are the way to go.

I had hair trimmers that I think use Ni-cds. One is really tough to replace so I didn;t when it died. Dunno about the other one. One was Remington and the other Norelco, I have an old National Semiconductor LED RPN calculator that uses Nicds (soldered in), This year I replaced 4 Ni-cd packs in the phones. One lasted 8 years, but usauslly get 4 to 5 years out of them.

oral-b (toothbrush) has a special take-apart disposal mode, Not successful putting them back together, I have no idea about a Phillips Airfloss. Both basically sealed against water.

Two UPS's have SLA batteries. The Trip-lite doesn't even work in non-UPS mode with the batteries dead. Not sure about the APC. One was free (dead battery) and the other was like ($10) at a thrift store. So, it takes a $20 battery, VA rating is something like 500 W.

For giggles, since we are on power sources, I made a up a box using a Chinese step-down converter with V and I meters that uses a 5.5/2.1 or 5.5/2.5 inputs (I can switch polarity internally if required) and it uses an adapt-a-plug for output. If an adapter fries for a "critical" piece of equipment (typically network stuff), I can make a replacement usually with a 12 V adapter. I do have two network gizmos that aren't in service yet that use like 19 V.

At some point, I want to make a low voltage UPS using this platform. https://www.mini-box.com/OpenUPS I haven't selected a battery yet. I want to use at least four of the the Chinese step down converters and probably a Li-Po battery. I basically want a slim form factor to hide behind a piece of furniture close to the wall mostly to power a WIFI repeater. I want to do something with the plugs, but not sure what yet to prevent the wrong voltage out with over current protection. Internally it will be 24V wit 4 step down converters.

So,I want some sort of (box with a plug) that attaches to my LOW voltage UPS with say pots to select an overvoltage and current and polarity, if it's not in range, there will be no output. I could even put the programming resistors in the "box" which isn't a bad idea, but I still need an overcurrent shutdown to protect against an adapt-a-plug being reversed.

I finally tidied up my network stuff which is a "bunch of wallwarts" and put them on a shelf with two octopus cords in the rafters. I have no intermittents anymore. US plugs suck when it comes to wall warts. The European sockets seem to be much better being recessed.

Hi again,

Well the delta V is for the NiMH and possibly NiCd, but not for Li-ion which would be nice to be able to set the voltage for.
Will it do 2 amps for all four batteries at the same time? Sometimes they allow higher current for less cells and lower current for all the cells at the same time, like 1 amp.

"The drill is a NiCd pack. I don;t use the drill much, but the two packs do OK. Two packs are the way to go."
Been there too, the drill came with two packs. Both died, fixed one, that died 5 years later, moved away from NiCd. Now use Lead Acid and i have several batteries including a jump pack, and it runs from the car 12v battery too now.

 

[KeepItSimpleStupid]

The adapter supports 3 Amps. A coax power jack usually supports < 5A. SO, don;t know about more than 1 at 2A. I would suspect not.

Manual says delta V for NiCd and Ninh and deviation < 0.03V @ 4.2 V CC/CV for Li-Ion.

6 temperature sensors are used which also activate the fan.

 

[MrAl]

Hi again,

Ok ok, well it's still a nice looking charger. I'll probably end up extending mine to two cell bays and leave it at that.
How much does that unit cost BTW in USD ?

 

[audioguru]

The replacement of the 600mAh Chinese Ni-Cad cells in my garden lights with Energizer 2300mAh Ni-MH cells keeps the garden lights lit until sunrise. My dogs wake me every day a few minutes before sunrise. I have a good view of the huge red sun.

I have a pair of cordless phones that came with Ni-Cad packs of three "2/3 AA" cells. After a few years a phone would quit after operating for only a couple of minutes. I replaced both batteries with Ni-MH packs from Philips which operate a phone longer than I can talk. Since the batteries cost as much as the phones then I considered replacing the phones but they are cheap. Chances are that new phones won't work and will need replacement a more few times than replacing their cheap batteries.

My electric screwdriver has a Lithium battery and it works perfectly.

 

[KeepItSimpleStupid]

Charger: **broken link removed**

So, about $55 from DealExtreme with free shipping. Shipping was fast.

 

[MrAl]

The replacement of the 600mAh Chinese Ni-Cad cells in my garden lights with Energizer 2300mAh Ni-MH cells keeps the garden lights lit until sunrise. My dogs wake me every day a few minutes before sunrise. I have a good view of the huge red sun.

I have a pair of cordless phones that came with Ni-Cad packs of three "2/3 AA" cells. After a few years a phone would quit after operating for only a couple of minutes. I replaced both batteries with Ni-MH packs from Philips which operate a phone longer than I can talk. Since the batteries cost as much as the phones then I considered replacing the phones but they are cheap. Chances are that new phones won't work and will need replacement a more few times than replacing their cheap batteries.

My electric screwdriver has a Lithium battery and it works perfectly.

Hi again,

My cordless phone takes two AAA cells, only NiMH not NiCd. I replaced the ones that came with it with some off brand low self discharge cells, but unfortunately the AAA cell size does not hold much charge no matter how good they are so the phone needs charging if it is left 'off the hook' for more than about 3 days. I wish they had AA cells in there instead.

I meant to check out the Lithium battery cordless drills but never got around to it because they were a little high priced. I think they have dropped somewhat now, but since i use Lead Acid with my older drill and it works pretty darn good i dont think i will switch over any time soon unless i see a really really good price. The cells used in such a device have to be high quality too, the high discharge rated Li-ion not the usual run of the mill Li-ion so that might have something to do with the price.

 

[MrAl]

Charger: **broken link removed**

So, about $55 from DealExtreme with free shipping. Shipping was fast.

Hi again,

Ok i looked up some of the specs and related and found that it charges the 18650 at 1 amp, and the wall wart is rated at 12v at 3 amps so that's 36 watts, and each battery is around 4v when charging at 1 amp, so that's 16 watts for 4 batteries so i would think it would do all 4 batts at 1 amp which isnt too bad really. It could charge the larger size Li-ion at 2 amps. 16 volts at 2 amps is 32 watts so it could probably do all four of those at 2 amps which is nice, although i dont need those cells right now.

The reviews are disturbing though, that say that there are oscillation issues and other issues. They mention that the Li-ion charge ok in the center two slots but may not charge properly in the outer two slots.

Also and more to my original point, if i bought a charger like this i'd like to be able to adjust the voltage. The reason for this is because the cells last longer if only charged to 4.15v as compared to 4.20v, and i see this charger spec is 4.200v plus or minus 0.030 volts. Well if it was minus then it would be 4.17v which would be nice for me, but if it was plus then it would be 4.23v which i consider too high.

One more side issue is that with the voltage not being adjustable that means we can not charge the new ultra high capacity Li-ion cells which have a termination voltage of 4.300 volts not 4.200 volts. In this case they would not charge enough.

They also mention that it can test the batteries too, and one test i guess is the internal resistance, but then they go on to say that the "slider" type contacts add too much resistance to the slots for a good test like this. I noticed this myself with some cell holders. The holders where not too bad but did introduce about 0.025 ohms per contact which changes the charging profile a bit and in a resistance test this would have to be compensated for somehow (maybe subtraction would be good enough if it was repeatable).

I dont know what they mean by "software" either when they talk about this charger. Does that mean it runs from the PC computer somehow too, as with some sort of settings software or something? If so, maybe there is a way to adjust the voltage somehow some way.

 

[KeepItSimpleStupid]

Termination voltage: Can't comment, but if that was your only issue and a show-stopper, you could hack that to a lower value. A double sided PCB between the two battery contacts, plated preferably. And an external circuit to cut power. Termination voltage could be Kelvin too.

Agree with the ESR measurement, but at least you know when to throw out a battery. Kelvin contacts would overly complicate things.

Software: Firmware. Mine flashes a 2.0 briefly on power up indicating the firmware version. I haven't taken it apart.

After the cells charge, you can measure Volts, mAh and how long it took to charge. Two new AAA Ni-mH cells: V=1.47, 1.45; mAh=1017, 1067; Time: 2:12, 2:26 charged at 500 mA rate. FDK from DIgi-key. No mAh on battery. No p/n on battery (HR-4U). Green/black writing, an impossible color combination. Digikey p/n ST153-ND 930 mAh. Time to get out the labelmaker (capacity, date, p/n and where purchased)

 

[audioguru]

I like Energizer batteries because they give me coupons and free samples. I dislike Duracell batteries because they leak all over the place.
Yesterday I bought some Energizer AA alkaline cells (holds power for 10 years while not in use). They have a sticker that says, "No Leaks for up to 2 years after a full discharge GUARANTEED or we will repair or replace your device (max $250.00)".

 

[MrAl]

Hi again,

KISS:
Something to think about i guess. With my own design though (or some other's off the web even) we get full control over how the charge will go, i guess that's why i always end up building my own. I dont build a lot of my own stuff anymore, but some things i just have to do myself

Audioguru:
That sounds pretty good. I dont usually buy the high end 'name' brand alkaline cells anymore though as i find the cheaper strange name large packs work pretty good for a lot less money. I use rechargeables for most stuff these days anyway.
I had problems with Rayovac alkies leaking, even to the point of thinking about never buying them again. They were always on sale.

 

[KeepItSimpleStupid]

Maybe I should have lined all of my ducks in a row and took pictures before I recycled about 5-10 lbs of batteries today. I would have had a nice distribution.

Somethings you really have to watch out for like Maglite flashlights. Some old models just won't fit the battery dimensions. A simple paper layer as part of a "new and improved" design makes certain batteries not work. Ever find the specs on the battery itself. Nah.

What's everyone's opinion about using rechargeable batteries or best bettery in general in flashlights? Let's also include flashlights stored in the car.
i.e. AA and D sizes.

 

[jpanhalt]

What's a flashlight? I use the "on-sale" LED lights from Harbor Freight.

As for cheap batteries, they would have to cost less than the aforementioned lights before I would consider them.

Now, for equipment that matters, I use high quality batteries. The damage caused by a cheap battery leaking is just not worth the savings for a $200 laser level.

John

 

[MrAl]

Hi again,

I use AA NiMH cell flashlights and 18650 cell flashlights, and never would waste my money on D cell flashlight batteries. I have a two D cell flashlight and a four D cell lantern both i've been meaning to convert to another battery type and size.

My lights either take 1 AA, 2 AA's, 3 AA's, 4 AA's, or one 18650, two 18650's, three 18650's, or four 18650's.
I also use AAA flashlights though but very rarely, like the ones you get on sale at Home Depot.
I use AA NiMH when i need AA size and rarely AA alkaline, and rarely AAA alkaline when i need AAA size which is rare.
All the lights i have that i still use have either multiple 5mm LEDs, one 5mm LED, or high powered 3watt or 10 watt LEDs either one or seven, and one dual high powered light that i run for general lighting off of a wall wart.
Oh yeah, i also made an emergency long term LED light using a lead acid battery. It will run for a few months without needing a charge, at least one month with full brightness.

For the car i dont ever store a flashlight in there because the batteries would have to put up with intense heat in the summer time and extreme cold in the winter. The heat would quickly ruin any batteries i have.

A way to deal with the heat/cold in the car is to make an LED light that plugs into the cigar lighter with enough cord length. That way you always have a light unless the main car battery runs down, but even if it does not start the car it will probably still run a regular size LED light as long as it is not totally dead. I always carry at least one LED flashlight with me though anyway. There is always the crank type flashlight too, but mine has an internal Li-on cell so that's not a good idea either. Maybe one with a super cap instead.

One caution about the 18650 size, some come with "flat" top and some come with "button" top (positive terminal). For many flashlights you need the button top type cells as the flat ones dont work in some lights and in other lights they might work when new but might be dangerous if the plastic wrapper at the top of the cell becomes worn because it can then easily short out.
People have come up with various ways to convert the flat tops to pseudo button tops, but with varied success and some ways (like using small magnets) can be dangerous if the magnets shift when the light is dropped or nudged too hard as that can cause them to short out.

 

[audioguru]

I use AA NiMH when i need AA size.....
For the car i dont ever store a flashlight in there because the batteries would have to put up with intense heat in the summer time and extreme cold in the winter. The heat would quickly ruin any batteries i have.

My son bought a high power single AA cell flashlight for me. It has adjustable focus. I use it in the evenings in winter. It has been in my car all summer since last winter and I used it yesterday evening (sunset is early now). Its Energizer AA Ni-MH cell has held its charge for a long time over a wide temperature span.

One caution about the 18650 size, some come with "flat" top and some come with "button" top (positive terminal).

I guess you have seen videos of fake Lithium battery cells like this video:

 

[MrAl]

Hi Audioguru,

Interesting video, i had not seen that one yet. That's also an extreme example. I've seen other 'fakes' that act more like the real thing but have safety issues. I've seen a few explode on the web in various videos. Many were over charged and some were shorted out. After a while they (18650) spew out sparks that look like a 4th of July fireworks demonstration