Rechargeable batteries and charger questions..

[TheGizmo]

I don't know much about rechargable batteries but I'm in the market for a 24-pack of ones that will last a long time without having to charge them. I do understand that there is a certain mah rating..and the higher the better.

I'm mainly looking at AA batteries..

What is the highest mah I can get in the AA?

I have a charger from Energizer that I got a long time ago from walmart.. it came with 4 rechargeable batteries, none of which seem to hold much of a charge anymore. I feel like I have to swap out my wireless mouse/keyboard/wii controller/gamecube controller batteries way too often. I guess they are about a year old.

Will my Energizer charger work with all different mah size batteries or is it specific to the batteries that came in the box with the charger... ie. I don't want to undercharge a battery that has a higher mah than what came with the charger. Basically I'm wondering if there is a certain time limit cut-off when the charger stops charging or if it checks to see if the battery is full before turning off.

Last question.. can you mix and match different mah batteries in the same charger at the same time?


Thank you, for any help, and if you know of a particular set of very good rechargeable batteries that will last a long time at a reasonable price, let me know what the link/site I can find it at.

Thanks again,
Gizmo

 

[holden j caufield]

got some 2500 mah energizer and duracells. Any charger works got like 12 of them and have prob saved myself $100 in batteries. Must have for the 360 wireless controllers.

 

[Muse]

Originally posted by: TheGizmo
I don't know much about rechargable batteries but I'm in the market for a 24-pack of ones that will last a long time without having to charge them. I do understand that there is a certain mah rating..and the higher the better.

I'm mainly looking at AA batteries, but maybe some D size ones too.

What is the highest mah I can get in the AA?

I have a charger from Energizer that I got a long time ago from walmart.. it came with 4 rechargeable batteries, none of which seem to hold much of a charge anymore. I feel like I have to swap out my wireless mouse/keyboard/wii controller/gamecube controller batteries way too often. I guess they are about a year old.

Will my Energizer charger work with all different mah size batteries or is it specific to the batteries that came in the box with the charger... ie. I don't want to undercharge a battery that has a higher mah than what came with the charger. Basically I'm wondering if there is a certain time limit cut-off when the charger stops charging or if it checks to see if the battery is full before turning off.

Last question.. can you mix and match different mah batteries in the same charger at the same time?


Thank you, for any help, and if you know of a particular set of very good rechargeable batteries that will last a long time at a reasonable price, let me know what the link/site I can find it at.

Thanks again,
Gizmo

AA's go up to around 2400 mah, even higher, maybe 2800 mah. Last time I checked there were 2-3 brands of rechargables that are excellent at maintaining charge. They are Sanyo Eneloops (the best) and Rayovac Hybrid's, and there are probably others by now. I have 4 Rayovac AA's and 4 AAA's. They don't hold a charge quite as well. The Eneloops hold around 85% of their charge one year after charging, which is phenomenally better than typical NiMH batteries, which typically lose that much in 2-3 weeks, I believe.

Since you will be making a decent investment in batteries, you should get a new charger. I have the La Crosse BC-900 (got it at Amazon.com), which is a fantastic charger for the money. It's something of a geek's charger, because it is configurable and can tell you a lot about the condition of your batteries. You can also pick from a lot of different charge rates.

My charger will do AA's and AAA's and it is mix and match, up to 4 cells. The charger actually came with adaptors. For instance, if I need a D battery, I can use a AA and put it in the supplied adaptor and use it as a D battery. Maha makes good chargers, and there are a number to choose from.

For further info you can check out www.batteryuniversity.com and the candlepower forums.

 

[ElFenix]

the best cheap charger is the lacrosse bc-900

the nicest AA batteries are the sanyo eneloops.

 

[FrustratedUser]

www.batteryspace.com

Great batteries for cheap.

 

[dighn]

Originally posted by: ElFenix
the best cheap charger is the lacrosse bc-900

the nicest AA batteries are the sanyo eneloops.

Ditto, or equivalent low self discharge batteries from other brands

For low average power applications such as "mouse/keyboard/wii controller/gamecube controller", you want low self discharge batteries. Regular NiMH batteries drain themselves quickly even if left unused.

 

[0roo0roo]

i use hybrid/precharged/enloop type batteries. basically same name for low self discharge nimh's. older nimhs lost 1% a day or more
also a 15 minute Duracell charger.. its cooling fan vents are pretty wide so it keeps the batteries pretty cool during charging, and 15 minutes makes charging something you don't have to remember in advance.. so two big negatives of rechargeables are pretty much solved. some might complain the 15 minute chargers bake batteries but i don't think so, i've felt hotter batteries in slower chargers because they don't have active cooling, plus at the cost per charge even if the life is slightly shorter the convenience wins.

 

[TheGizmo]

Ok.. cool lot of good information here, which calls for more questions.

Are all AA size rechargeable batteries NiMH or is there is a Li-Ion kind?

Also.. researching for just a few minutes on Amazon.com, I found that La Cross BC-900 charger for $39.99 is that a good price? I'm not sure I want to invest that much in a charger if my current charger will work just as good but take a little longer. I don't care much for adaptability to bigger sized batteries either.. AA is probably going to be the only kind I charge on a daily basis. The D batteries I've decided to hold off on getting rechargeables for.

My current energizer charger will fit AA and AAA so that takes care of that part.

Does that La-Cross charger really make the batteries last longer than a regular cheapo walmart one?

More questions to come... thank you for all the advice everyone.

 

[TheGizmo]

Oh.. and researching the eneloop batteries, I can only find ones that go up to 2000mah, while I've found other branded batteries that go up to 2600mah (targus brand).. Is this mah rating more or less a marketing scheme? Meaning do some better quality 2000mah batteries last longer than cheaper 2600mah batteries because of how they are designed?

 

[Kirby64]

Originally posted by: TheGizmo
Oh.. and researching the eneloop batteries, I can only find ones that go up to 2000mah, while I've found other branded batteries that go up to 2600mah (targus brand).. Is this mah rating more or less a marketing scheme? Meaning do some better quality 2000mah batteries last longer than cheaper 2600mah batteries because of how they are designed?

No. Higher mah = higher mah. Eneloops are better because they have a low self-discharge rate.

Regular NiMH batteries will discharge themselves A LOT if you don't use them (Almost halfway dead in a month). Eneloops use a slightly different technology that allows them to have a lower self-discharge rate. Despite the lower mah rating, they more than make up for it in the far far lower self-discharge rate.

 

[Muse]

Originally posted by: TheGizmo
Ok.. cool lot of good information here, which calls for more questions.

Are all AA size rechargeable batteries NiMH or is there is a Li-Ion kind?

Also.. researching for just a few minutes on Amazon.com, I found that La Cross BC-900 charger for $39.99 is that a good price? I'm not sure I want to invest that much in a charger if my current charger will work just as good but take a little longer. I don't care much for adaptability to bigger sized batteries either.. AA is probably going to be the only kind I charge on a daily basis. The D batteries I've decided to hold off on getting rechargeables for.

My current energizer charger will fit AA and AAA so that takes care of that part.

Does that La-Cross charger really make the batteries last longer than a regular cheapo walmart one?

More questions to come... thank you for all the advice everyone.

I don't know what kind of charger you have, other than the brand. If it's a fast charger, there's plus and minus. It charges faster but a faster rate causes a faster deterioration of the battery. The neat thing about the La Crosse is that it will optionally recondition your battery (Refresh mode). Or it will "Discharge" and then charge, of you choose that. Or it will "Test" the batteries, which amounts to charge/discharge/charge. Or it can straight "Charge." It shows you the capacity of the batteries when you are through, as well. So, if used well, it can significantly extend the life of your batteries. Showing you the capacity of each cell will allow you to match cells, always a plus. It takes a lot of the guesswork out of owning rechargeable cells, and that to me is great. Amazon sometimes (at least they used to), have sales on the La Crosse, where you can get it for $34.95. However, for the money, $40 for this is great, IMO.

There are rechargeable Li-ion batteries. More expensive, best for certain applications, and there are caveats. I don't recall hearing about AA's for them, though. They require chargers specifically designed for them, otherwise they are quite dangerous (can explode in a charger not designed for them).

 

[dighn]

Originally posted by: Kirby64

Originally posted by: TheGizmo
Oh.. and researching the eneloop batteries, I can only find ones that go up to 2000mah, while I've found other branded batteries that go up to 2600mah (targus brand).. Is this mah rating more or less a marketing scheme? Meaning do some better quality 2000mah batteries last longer than cheaper 2600mah batteries because of how they are designed?

No. Higher mah = higher mah. Eneloops are better because they have a low self-discharge rate.

Regular NiMH batteries will discharge themselves A LOT if you don't use them (Almost halfway dead in a month). Eneloops use a slightly different technology that allows them to have a lower self-discharge rate. Despite the lower mah rating, they more than make up for it in the far far lower self-discharge rate.

^ yep. it really depends on the average power draw. From some quick and dirty calculation, assuming 1% to 1.5% self discharge in the 2600mah while negligible in the eneloop, you need a device that lasts about 2-3 weeks for the MAH disadvantage to break even. I can't say how accurate this is but it looks ball park to me. For keyboard/remote, I would definitely say the lower MAH will be more than made up by the eneloop's attributes; they last months. I don't know about the game controllers though.

 

[jpeyton]

Not all batteries are created equal; batteries from a top tier company like Sanyo will outlast batteries with higher "mAh" ratings from other brands.

Sanyo makes 2700mAh high-capacity NiMHs, and 2000mAh low-discharge Eneloops.

Costco also has a deal on Eneloops:

8 x AA
4 x AAA
2 x C-cell adapter
2 x D-cell adapter
World Charger

$20

 

[mugs]

Originally posted by: ElFenix
the best cheap charger is the lacrosse bc-900

the nicest AA batteries are the sanyo eneloops.

I :heart: my BC-900. It's not exactly cheap by most people's standards, but it is cheaper than some other good chargers.

When I need high capacity (i.e. camera flash) I have Sanyo 2700s. They're a bit pricey; Batterystation 2300s are a good alternative at half the cost.

I also have a bunch of Eneloops and Rayovac Hybrids for low-self-discharge applications.

 

[Eli]

Do NOT skimp on a charger, it is the single most important aspect of rechargeable batteries.

 

[RossMAN]

Originally posted by: jpeyton
Sanyo makes 2700mAh high-capacity NiMHs, and 2000mAh low-discharge Eneloops.

Costco also has a deal on Eneloops:

8 x AA
4 x AAA
2 x C-cell adapter
2 x D-cell adapter
World Charger

$20

That's an awesome deal and I think it expires Monday 12/31/2007.

http://forums.anandtech.com/me...id=40&threadid=2125339

 

[Throckmorton]

Energizer's 15 minute charger is good because it charges each battery independently. This means you can charge an odd number of batteries, unlike some others. You can only use the 15 minute batteries made by Energizer and maybe the Duracell ones.

 

[MrPickins]

Looks like I'll be picking up a BC-900 soon.

 

[TheGizmo]

Originally posted by: RossMAN

Originally posted by: jpeyton
Sanyo makes 2700mAh high-capacity NiMHs, and 2000mAh low-discharge Eneloops.

Costco also has a deal on Eneloops:

8 x AA
4 x AAA
2 x C-cell adapter
2 x D-cell adapter
World Charger

$20

That's an awesome deal and I think it expires Monday 12/31/2007.

http://forums.anandtech.com/me...id=40&threadid=2125339

That does sound like a good idea to me. Too bad I don't have a CostCo membership.. anyone know if they let you do a 1-day trial shopping there. I thought I remember hearing that either CostCo or BJ's would let you have a 1-day shopping trial but you have to pay 10% more than what anything costs. I'd be willing to pay the extra 10% if they allow that. Anyone know?

Anyway.. really good information in this thread, I appreciate all the help. I think I'm set on getting the Eneloop 2000 mah batteries, and either use the charger that comes with the set at CostCo (provided I can buy it without membership).. or down the road invest in a BC-900. Eventually I think I will get the BC-900.. being able to test my batteries and recondition them sounds like one of the best things thats happened to rechargeable batteries in a while.

 

[mugs]

I don't think Costco does the one day trial thing.

 

[StageLeft]

Rayovac Hybrid 2100 slow-drain nimh are about $9 for 4 AA from walmart.

That la crosse charger is good and is what I use.

Duracell also has a slow-drain AA cell now, but still more expensive than Rayovac.

There are other AA cells like li-ion close, if not the exact same size, but you will need a charger set specifically for their chemistry to bring them to the correct voltage and of course will have a hard time finding a device to take those batteries (since their voltage is too high).

The only thing I'd like to add is that some time ago Rayovac had an IC3 line of battery that would charge an AA 2000 mah bat in 15 minutes. I have several of these and the associated charger. They're nearly four years old and still do indeed charge in a mere 15 minutes. I don't know why Rayovac dropped these high-charge bats, as they really are awesome for a frequently-used digital camera. I think energizer or duracell have a 15 min charger now, too, but I don't know why it didn't catch on in a big way, since it is a proven technology (though it probably accelerates loss of battery longevity).

 

[eelw]

I love my Eneloops. For my Kodak digital camera, standard alkalines will only last 10 minutes when recording HD video. For 2800mAhr rechargables, I get about 30 minutes. But with the Eneloops, I have 1:30 hours.

 

[0roo0roo]

Originally posted by: TheGizmo
Oh.. and researching the eneloop batteries, I can only find ones that go up to 2000mah, while I've found other branded batteries that go up to 2600mah (targus brand).. Is this mah rating more or less a marketing scheme? Meaning do some better quality 2000mah batteries last longer than cheaper 2600mah batteries because of how they are designed?

mah is just capacity. if you need max capacity now and you will use the batteries right after charging, than go for higher mah. but for regular more intermittent use the low discharge wins. lithium ion batteries you don't have to worry about. their voltage is different so only special applications are possible. generally 123a size. most C and D cell nimh are fake, just AA in a shell. look at the mah rating and you will know. real C/D are expensive and have much higher capacity, but regular consumers would not understand and would balk at the cost so they aren't sold in normal stores. only online really.

The only thing I'd like to add is that some time ago Rayovac had an IC3 line of battery that would charge an AA 2000 mah bat in 15 minutes. I have several of these and the associated charger. They're nearly four years old and still do indeed charge in a mere 15 minutes. I don't know why Rayovac dropped these high-charge bats, as they really are awesome for a frequently-used digital camera. I think energizer or duracell have a 15 min charger now, too, but I don't know why it didn't catch on in a big way, since it is a proven technology (though it probably accelerates loss of battery longevity).

ic3 probably got dropped because other brand chargers do any battery in 15 minutes. the chargers do cost more of course.

 

[jpeyton]

Originally posted by: 0roo0roo
ic3 probably got dropped because other brand chargers do any battery in 15 minutes. the chargers do cost more of course.

Or because charging a battery that fast is bad for the long-term health of the battery.

I'd rather buy a few extra cells and keep them handy. The best chargers take a couple hours to charge a pair of cells; actually, they fully discharge them, charge them at a moderate speed up to 95% of their capacity, then trickle charge them to top it off.

 

[0roo0roo]

naw, i think its just that they tried to push proprietary batteries on people. no one likes that.
esp when its been demonstrated that it wasn't necessary.
batteries are cheap.
whether the time baby a battery for a few more charges is worth it is personal preference. we are talking a cent a use here assuming 2.50 a battery at 250 charges. thats assuming reduced life even. i've seen charge cycle life stated at 500~ depending on source. so even if it supposedly reduced battery life span by half its not really something to worry about.