[tigger]

Try this http://www.onlybatteries.com/main.asp link for rechargeables

 

[Eagle_Driver]

Digging this thread up from dormancy...

There is one disadvantage of slow chargers, especially trickle chargers (which often require more than 24 hours to fully charge most NiMH batteries): If you use them as the sole means of recharging NiMH batteries, larger crystals will form on the battery electrodes, making the charging less efficient and less complete. Don't be surprised that what seems to be 'fully charged' using a slow charger alone is nowhere near as full as you think! (Like, an 1850mAh NiMH battery that's reaaaally sloooooow-charged will not perform any better or last any longer between charges than an earlier-generation 1400mAh NiMH battery that's been quick-charged in a 'smart' charger.) And extremely slow-recharging is actually damaging to the usable life of the NiMH batteries, by not allowing the batteries to become anywhere near fully charged - because more and more large crystals continue to form on those electrodes. In fact, I have had 700mAh NiCd batteries that have always been charged in such a trickle charger (one that delivered only 45mA of current even to AA batteries); it took all of 22 hours to 'fully' charge those NiCds, and the capacity dropped from 700mAh when new to only 450mAh after only 25 charge cycles! (And yes, I always have discharged those NiCds completely before recharging.) As a result, I'd recommend those trickle chargers only for topping off already charged NiMH batteries.

My RatShack 23-422 charger has been giving me good service - but it's very inconvenient for me to use, because I have often-used portable devices that use one AA battery or three AAA batteries - and I have to charge all three batteries as soon as they get discharged. But my charger only allows charging batteries in pairs (2, 4, 6 or 8 at a time) - and worse, all of the batteries to be charged in the 23-422 charger must be of exactly the same size, exactly the same capacity, and exactly the same chemical formula (which means that if I were to charge 1800mAh NiMH AAs in my RatShack charger, all of the other batteries being charged at the same time must all be 1800mAh NiMH AAs, as well). That will guarantee unevenly-charged sets of batteries.

So, this past Monday I ordered a Maha charger from Thomas Distributing (it's the successor model to the still-available C204F, the C401FS). The new C401FS has both negative-pulse charging and delta-slope termination (like a good smart charger should), eliminating the need for a separate discharge/conditioning cycle (helpful when charging partially discharged NiMH batteries - NiCd's still need full discharging for best results). Second, unlike the 204F (which still requires the batteries to be recharged in pairs), the 401FS can charge one to four AA or AAA batteries at a time - and with a separate charging circuit for each cell (unlike the one-hour chargers from Energizer and Ray-O-Vac, which actually use only one or two commonly shared charging circuits for all four cells). Third, the 401FS offers a choice of two charging modes: 'Fast' (which claims to charge 1700mAh AA NiMH batteries in 1 hour 40 minutes), and 'Slow' (which claims to take 5 hours for the same-capacity NiMH AAs). The charging current in 'Fast' mode is 1000mA for AA, 500mA for AAA; in 'Slow' mode, 300mA.

The charger is being shipped as I type my post here, and it's being shipped from downstate Illinois (yep, the same state that I live in). So, I'd expect it to arrive on either Friday of this week or Monday of next week. And yes, I will use the 'slow' mode most of the time, unless I need the fully-charged set of batteries in a hurry.

 

[grinch]

http://www.thomas-distributing.com/mhc401fs.htm

they have a new charger model, it seems. i think i'm going to go for one of those, and a couple of these: http://www.thomas-distributing.com/mh-4aa200.htm
for the new portable setup i'm running. the new 2000mah seem pretty impressive.

 

[Eagle_Driver]

I actually had the 401FS charger shipped FedEx Ground (not UPS Ground), and the FedEx Ground guys actually came Thursday and also came Friday! (But I still don't have the charger yet.) I was at work on Thursday, and I went out for a walk on Friday - and the FedEx Ground guys came right at those moments!

So, I'd better not go out tomorrow afternoon - at least not until the package arrives.

 

[NotoriousBIG_PJ]

Why get 2000 mAh when you can get 2100.

Biggie.

 

[Eagle_Driver]

Once again, I anticipated the package, but the FedEx Ground twats didn't even want to wait! They thought the doors were closed, and then moved on! So I went to their facility to pick up the package, and waited two hours at the facility!

So, I finally got the charger home, plugged it in, and proceeded to charge a 1500mAh RadioShack NiMH rechargeable battery in 'slow' mode. It's been charging for only about 15 minutes so far - but it seems to be working so far.

One very important difference between the operating procedure of the Maha chargers and RadioShack chargers: The Maha chargers MUST be plugged into either an AC wall outlet or a 12V DC cigarette-lighter socket BEFORE any batteries whatsoever can be inserted into them (but removing fully charged batteries from Maha chargers may be done with the charger still plugged in or unplugged). RadioShack's chargers, on the other hand, MUST have batteries loaded (in pairs with most of them) BEFORE they're plugged in - and they MUST be unplugged BEFORE any batteries are removed.

EDIT/UPDATE: The charger works as advertised! So far I've charged a few old RadioShack batteries - a 1500mAh AA NiMH in 'slow' mode (which took a little under 5 hours), and a couple of 850mAh NiCd AA batteries in 'fast' mode (they took just under an hour). In both cases, the charging light changes from red to green at the end of the cycle - and thus switching to trickle charge.

 

[bootman]

This site is running a sale.
I've used the charger and the 1850 batteries with my digicam and they work really well.

The deal is a charger with 12-1850 AAs for $47.

 

[Eagle_Driver]

Well, the charger in that deal is more of the 'fast/gentle' type rather than the 'fast/complete' type. Furthermore, it requires the cells be charged in pairs (like most chargers on the market) - but what if I have a device that uses three batteries?

 

[bootman]

Quote:

Originally posted by Eagle_Driver Well, the charger in that deal is more of the 'fast/gentle' type rather than the 'fast/complete' type. Furthermore, it requires the cells be charged in pairs (like most chargers on the market) - but what if I have a device that uses three batteries?

Use 6 in rotation?

I just thought the 12 AA included made the deal extra sweet.

 

[jedai]

Rayovac PS1 and PS3 chargers are affordable ($10 and $20, respectively) and widely available. They have separate charging circuits (and LEDs) for each cell and stop automatically when fully charged. See the following manufacturer link.
http://www.rayovac.com/products/recharge/chargers.shtml
PS1 charges up to four AA/AAA or one 9V cell (the link is inaccurate on this). PS3 charges up to eight AA/AAA, four C/D, or one 9V cell. I am using both and think they are of high quality, especially PS3. Why look elsewhere?

 

[Eagle_Driver]

However, those particular Ray-O-Vac chargers can take as long as 18 hours to fully charge 1800mAh AA-size NiMH batteries - and lack continuous trickle-charge capability.

 

[jedai]

The current version of Rayovac PS1 and PS3 chargers do have trickle-charge after the main charging cycle is complete. I agree that PS1 may take long to charge high capacity AA cells from empty. But PS3 is much faster and takes quite reasonable time to fully charge any size/capacity of cells. BTW leave the lid of the charger open when charging although the manual says otherwise.

 

[Eagle_Driver]

And as I've noticed, both of those Ray-O-Vac chargers are becoming increasingly more difficult to find in my area. While the stores in my area stock the PS1 model, nobody carries the PS3 model at all. And the rechargeable C and D batteries are far less popular than the rechargeable AA and AAA batteries. And even with the smaller chargers, the slower, cheaper chargers are becoming harder to find: Both Ray-O-Vac and Energizer are pushing their 1-hour chargers (which, I know, can - and do - severely overheat the batteries, depending on the cell construction).

And none of the Ray-O-Vac chargers are 'smart' enough, IMHO: They rely on a simple 'capacity sensor' circuit like the ones built into most portable audio gear, which allows some degree of overcharging - but without any truly 'smart' means of terminating the charge.

 

[jedai]

Rayovac doesn't disclose the detail of its charging scheme for their chargers. But PS1 and PS3 must NOT be doing simple "capacity sensing" scheme. When I charge multiple cells of same type/capacity, each cell completes charging in different time. They most likely sense the delta-curve to determine full-charge for each cell. Otherwise, I wouldn't say these are high quality chargers. Most other chargers on the market are timer based and/or of two cells per charging circuit type. I think PS1/PS3 are just as smart as the smart charger that you are refering to. The build quality of these chargers are excellent; I don't think it is very profitable on selling them in such low prices.

 

[Eagle_Driver]

And I think I know why Ray-O-Vac can get away with setting such a low price on its 'smart' chargers with independent charging circuits for each cell: They are NOT 'quick' or 'fast' chargers by design, but they are actually slow chargers by their nature. 1800mAh AAs charged in the PS1 charger can take all of 18 hours, and even the PS3 needs more than six hours to fully charge such batteries. (The Maha C124S charger, which sells for $8.95 plus shipping at Thomas Distributing, is similar to the PS1 charger, except that the C124S has a constant low charging rate - no automatic shut-off - instead of a true trickle-charge mode.)

On the other hand, the Ray-O-Vac one-hour charger sells for a relatively low price compared to what most other one-hour chargers sell for - because that charger actually uses one single commonly shared charging circuit for all four cells even though you can charge one, two, three or four cells at a time, and then charges the cells in parallel, and furthermore bases the total charging time on the strongest cell in the load, so that weaker cells get overcharged. Thus, I find it okay only for charging one cell at a time.