NiCD with High MaH?

[ohmygahitscoby]

I've noticed that most NiCD batteries don't have high MaH's. The ones that do are NiMH, LiPo, Li-Ion, etc. Does anyone know if there is a high MaH NiCD battery or if it is non-existent?

 

[Lessen]

I would guess it's almost non-existant. Nicd's are a thing of the past and I don't use a single one anymore, not even in my glow ignitor. Nicd's can't be fast charged, only trickle charged. Therefore, the higher the mah rating the longer it will take to charge. The same is true for any battery but since it can't be charged quickly it was be an insanely slow process. I can't imagine waiting for a 4200 mah Nicd battery to charge

 

[ohmygahitscoby]

Really? I have a fast-charging charger for my NiCD's. It's a 15 minute charger, but it only chargers about 1000 MaH.

Edit: Never mind. That's just a timer, not a fast charger.

 

[HeartBreak]

I would guess it's almost non-existant. Nicd's are a thing of the past and I don't use a single one anymore, not even in my glow ignitor. Nicd's can't be fast charged, only trickle charged. Therefore, the higher the mah rating the longer it will take to charge. The same is true for any battery but since it can't be charged quickly it was be an insanely slow process. I can't imagine waiting for a 4200 mah Nicd battery to charge

Wrong-o me amigo. I charge my 2400mah nicads at 4.5A. They're about 7 years old, and still take a charge like they were new. Perhaps you're thinking of the old Cadnica "yellow SCE" cells of yore.... Those required a charge of no more than .2A, or they would hiss-and-pop. Duratrax still markets them (amazingly!).

The only major differences between nicad and nimh are the discharge characteristics. Nicads tend to have a surge at first, decline gradually, then suddenly "dump". Nimhs, on the other hand, maintain a more "steady" rate throughout the charge.

If memory serves, about the highest MaH rating in a NiCad you'll find is about 2600 or 2800mah (I can't remember, been forever since I battery-shopped). Nimh, on the otherhand.... I wouldn't be surprised if they punch the 5000mah barrier before the end of the year.

 

[Lessen]

Very interesting my friend.. I've always been under the impression that Nicds didn't like to be fastcharged. I know when I first got my buggy a couple years ago I bought a couple 1100mah Nicads for my starter box but my charger absolutely would not fastcharge them. both my charger and the packs were brand new and I tried to charge 'em up at the track but it just wouldn't do it. Maybe I just had some crap packs.. they were el cheapo's.... Oh well, can't be right all the time

At any rate, I don't think any of my LHS's carry a Nicd over 1800mah. You just don't see very much of it.

 

[CharliesTheMan]

Wrong-o me amigo. I charge my 2400mah nicads at 4.5A. They're about 7 years old, and still take a charge like they were new. Perhaps you're thinking of the old Cadnica "yellow SCE" cells of yore.... Those required a charge of no more than .2A, or they would hiss-and-pop. Duratrax still markets them (amazingly!).

The only major differences between nicad and nimh are the discharge characteristics. Nicads tend to have a surge at first, decline gradually, then suddenly "dump". Nimhs, on the other hand, maintain a more "steady" rate throughout the charge.

If memory serves, about the highest MaH rating in a NiCad you'll find is about 2600 or 2800mah (I can't remember, been forever since I battery-shopped). Nimh, on the otherhand.... I wouldn't be surprised if they punch the 5000mah barrier before the end of the year.

They already have a 5000 out that you can buy right now. It's made by Venom. It's the bigest on I've looked at, but there may be bigger and I just didn't see them,

http://cgi.ebay.com/Venom-5000mah-5...ryZ44028QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

[ohmygahitscoby]

Yeah, I was gonna say that. Wow, my LHS sells those for fcking $80. I could get almost half the price online!

 

[Rolex]

I had a couple of 1500 NiCads for an electric rustler several years ago and I got a 3000 for it. It cost me $65.

NiCads can be charged at double their rating, and it's the NiMH batts that can only be charged on an even rate. 3000 mAH, 3 Amps. With NiCads you can charge a 1500 at 3 amps.
Correct me if I'm wrong, but that's the way I've been told, and that's the way I've done it. I haven't lost a battery yet.

 

[HeartBreak]

Very interesting my friend.. I've always been under the impression that Nicds didn't like to be fastcharged. I know when I first got my buggy a couple years ago I bought a couple 1100mah Nicads for my starter box but my charger absolutely would not fastcharge them. both my charger and the packs were brand new and I tried to charge 'em up at the track but it just wouldn't do it. Maybe I just had some crap packs.. they were el cheapo's.... Oh well, can't be right all the time

At any rate, I don't think any of my LHS's carry a Nicd over 1800mah. You just don't see very much of it.

They most likely used the SCE cells (which are amazingly still being produced) in the pack. Good ol' SCR's (red) and SCRE's (the higher capacity nicads) love to be charged with a higher rate.

It could be due to the low internal resistance that your charger thought they were AA nicads (since the rating is that of my AA nicads that I have for my M8). That would explain the slower charge rate.

 

[Lessen]

They most likely used the SCE cells (which are amazingly still being produced) in the pack. Good ol' SCR's (red) and SCRE's (the higher capacity nicads) love to be charged with a higher rate.

It could be due to the low internal resistance that your charger thought they were AA nicads (since the rating is that of my AA nicads that I have for my M8). That would explain the slower charge rate.

Yeah, maybe that was the case. At any rate, I guess I just figured if I couldn't fast charge those Nicd's then Nicd's couldn' be fastcharged. I suppose that explains why they were like $10 packs.

NiCads can be charged at double their rating, and it's the NiMH batts that can only be charged on an even rate. 3000 mAH, 3 Amps. With NiCads you can charge a 1500 at 3 amps.
Correct me if I'm wrong, but that's the way I've been told, and that's the way I've done it. I haven't lost a battery yet.

You know there is sooo much information on battery charging out there it's no wonder people get confused. That's what I thought about Nimhs too Rolex but then at the same time I've read articles where people are charging their Nimhs significantly higher than their rating... like a 4200 pack at 5 or even 6 amps. I dont' get it.. I hear something different everywhere I turn. I figure it safe to charge my Nimhs at any even rate, to my understanding that will provide longer life anyways.

 

[robmob]

Normally I charge my Nimh packs at the mah rate or less.

However, on race days I will charge them at 5 or even 6 amps between heats and have not had any problems doing so.

I will be switching completely to Lipo this year, but my son will still be using Nimh packs.

 

[Cupooterluvr]

Yeah, maybe that was the case. At any rate, I guess I just figured if I couldn't fast charge those Nicd's then Nicd's couldn' be fastcharged. I suppose that explains why they were like $10 packs.



You know there is sooo much information on battery charging out there it's no wonder people get confused. That's what I thought about Nimhs too Rolex but then at the same time I've read articles where people are charging their Nimhs significantly higher than their rating... like a 4200 pack at 5 or even 6 amps. I dont' get it.. I hear something different everywhere I turn. I figure it safe to charge my Nimhs at any even rate, to my understanding that will provide longer life anyways.

I charge my RC18t pack (1200mah NiMH) at 2 amps and sometimes even 4 amps when I don't feel like waiting. My Dynamite Prophet Plus charges it up fully every time. I get probably 10-15 minutes out of a pack.

At 4 amps the battery doesn't even get warm, although the wires connecting the battery and charger do

 

[platgof]

So how long would it take to charge a 2300 nimh pack at 2.3 amps?

 

[CharliesTheMan]

I was expecting to give a wrong answer, shouldn't have given one at all.

 

[HeartBreak]

i'm no pro, wouldn't that be 10 minutes?

Nopers, more around an hour. It takes me about 25 minutes to charge a 2400 at 4.5a.

 

[CharliesTheMan]

I read a formula yesterday on figuring out how to determine proper charge time, but that will only work if the battery is completely drained. A quick search of the internet would probably produce the formula. I'm not a math person and obviously screwed it up.

 

[HeartBreak]

Nah, it's no big deal. Like you said, it doesn't take into account the 5% left in the nicad before charging. Even then, charge time can vary widely, depending on delta-peak value and power supply amperage.

I tend not to put much math into stuff... It's easier just to charge a pack and guestimate the time .

 

[platgof]

I got some 2300 nicad and charged them at 4.5 amps, no problem.