Eneloops: what charger do I need? (info and discussion thead)

[Azazel]

Order it from GearBest. We're a global economy now. I once shipped a Mark Levinson DAC to a guy in Nagasaki, Japan and it got there just fine. Imagine that?

Chris

Ive only gone and ordered it!

 

[crimsondr]

Hi all,

I had a La Crosse BC500 charger that I used for my eneloops but it has completed died after 1.5 years of minimal use. Now looking for a new charger and doing a lot of reading. From what I've read trickle charging and PWM based charging is bad for eneloops. So here are my questions:

1. The two main chargers I was looking at, Maha MH-C9000 and Opus BT 3100 both trickle charge at the end of a cycle. If trickle charging is so bad for eneloops why are these chargers recommended?
2. Both these chargers also use PWM based charging, so again why are they recommended?
3. If trickle charging is bad for eneloops, why would you ever use the break-in mode of the maha mh-c9000?
4. Is there a recommended charger that does not trickle charge at the end of a cycle and does not use PWM when charging?

Thanks.

 

[SilverFox]

Hello Cimsondr,

Welcome to CPF.

The trickle charge rate of the C9000 is quite low. Extended trickle charging is not recommended but if you are going to leave the cells overnight a low trickle charge rate is much better than a higher trickle charge rate.

The Break In mode is an attempt to follow the industry standards for determining cell capacity. It also serves to revitalize a cell that has been in storage. Using the Break In mode every time you charge is not recommended, but utilizing it every year or every two years in an attempt to track the condition of your cells gives you an idea of where you are at.

Tom

 

[crimsondr]

Hello Cimsondr,

Welcome to CPF.

The trickle charge rate of the C9000 is quite low. Extended trickle charging is not recommended but if you are going to leave the cells overnight a low trickle charge rate is much better than a higher trickle charge rate.

The Break In mode is an attempt to follow the industry standards for determining cell capacity. It also serves to revitalize a cell that has been in storage. Using the Break In mode every time you charge is not recommended, but utilizing it every year or every two years in an attempt to track the condition of your cells gives you an idea of where you are at.

Tom

Thanks for the info. I just finished testing a couple AAA eneloops that are a few years old. I typically put batteries in the kids toys and forget about them. I first did a refresh analyze on them and they both came back with less than 200mAh capacity. I then did a break-in and now they both come back with over 600mAh capacity! So looks like this charger can certainly help restore cells!

 

[BloodLust]

Oops. Wrong thread.

 

[peahi]

BQ CC57 looks sweet.

When does this charger come out in the US? This looks very promising for daily use and for emergencies (able to recharge a smartphone).

 

[Climb14er]

Been using a Maha C9000 charger for years, charging my Eneloops. Works great, totally reliable, easy to change settings, does an excellent job. Highly recommended.

 

[ScottJD]

When does this charger come out in the US? This looks very promising for daily use and for emergencies (able to recharge a smartphone).

I just picked up a Costco pack that had 8 AA, 4 AAA and the BQ-CC55 charger for $20.
It had an instant $10 rebate, so this may not be the same for all Costco stores and Costco online is still $30.
I've never had an eneloop get that warm when charging, but I can say this charger does get them warm. Of course it's charging over twice as fast as the CC17 ones I own. I think it's the main reason I bought the pack.
I have also seen the CC55 on eBay for about $12-$14
I would be concerned about them getting warm, but it's inky warm and nothing like the old royavac 15 minuite fast chargers. Those would be so hot it would burn your hand if you didn't let them cool down first.

The good news is not only does it check the starting voltage, it is doing 750mA per each cell when it has 4 AA, and I was able to confirm and measure 3.033A when I was testing it. It seems to put out full power if you dead short a bay. So we know it can do 3A and it's a true 750mA each. Now it says it will charge 4AA in 3 hours, and 2AA in 1.5. So it might be putting out 1.5A per cell when it only has 2AA charging? I'm sure then two will get even hotter. But I quick tear down reveled it has two thermistors measuring the temperature. One between bay 1 and 2, and another between bay 3 and 4. I don't know if it will shut down once it reaches a dangerous temp or ifs it's doing an active charging method my monitoring the temperature and decreasing the current on the bays that are getting over a certain temperature?

It has a lot more active circuitry on the board, bigger caps, and of course a bigger transformer. But I didn't take the time yet to identify each chip or even partially reverse engineer it.
I was glad to see the temperature monitoring, something the old one was missing.
It also has great separation in between the AC and DC side with a plastic blast shield and a high voltage cutout in the PCB. It looks nicely designed and thought out.

The highest temp I measured so far on the charger with the case on it was 40C, the hottest battery was 44C and thus is from a set I bought over a year ago, maybe abut 14 months ago? The temp measurement were taken with my FLIR. The newer ones seem to be cooler despite either set seeing much full drain and recharges. No wear near 2000 cycles yet. But now that I can charge them faster I think they will start getting more use. Well that and I'm finally almost out of the industrial alkaline pack I bought so standard stuff will start unsung the eneloop S also like TV remotes.

I hope some of this helped,
Scott

 

[speedlever]

I just picked up a Costco pack that had 8 AA, 4 AAA and the BQ-CC55 charger for $20.
It had an instant $10 rebate, so this may not be the same for all Costco stores and Costco online is still $30.
I've never had an eneloop get that warm when charging, but I can say this charger does get them warm. Of course it's charging over twice as fast as the CC17 ones I own. I think it's the main reason I bought the pack.
I have also seen the CC55 on eBay for about $12-$14
I would be concerned about them getting warm, but it's inky warm and nothing like the old royavac 15 minuite fast chargers. Those would be so hot it would burn your hand if you didn't let them cool down first.

The good news is not only does it check the starting voltage, it is doing 750mA per each cell when it has 4 AA, and I was able to confirm and measure 3.033A when I was testing it. It seems to put out full power if you dead short a bay. So we know it can do 3A and it's a true 750mA each. Now it says it will charge 4AA in 3 hours, and 2AA in 1.5. So it might be putting out 1.5A per cell when it only has 2AA charging? I'm sure then two will get even hotter. But I quick tear down reveled it has two thermistors measuring the temperature. One between bay 1 and 2, and another between bay 3 and 4. I don't know if it will shut down once it reaches a dangerous temp or ifs it's doing an active charging method my monitoring the temperature and decreasing the current on the bays that are getting over a certain temperature?

It has a lot more active circuitry on the board, bigger caps, and of course a bigger transformer. But I didn't take the time yet to identify each chip or even partially reverse engineer it.
I was glad to see the temperature monitoring, something the old one was missing.
It also has great separation in between the AC and DC side with a plastic blast shield and a high voltage cutout in the PCB. It looks nicely designed and thought out.

The highest temp I measured so far on the charger with the case on it was 40C, the hottest battery was 44C and thus is from a set I bought over a year ago, maybe abut 14 months ago? The temp measurement were taken with my FLIR. The newer ones seem to be cooler despite either set seeing much full drain and recharges. No wear near 2000 cycles yet. But now that I can charge them faster I think they will start getting more use. Well that and I'm finally almost out of the industrial alkaline pack I bought so standard stuff will start unsung the eneloop S also like TV remotes.

I hope some of this helped,
Scott

I bought this charger yesterday and today, stumbled across this review which doe NOT recommend the CC55 due to lack of thermal management.
https://www.filterjoe.com/2017/03/11/best-budget-chargers-bqcc55-fct344-bqcc17/

This charger seems pretty finicky about the batteries it will accept too as it won't accept my older rechargeable AA NiMH batteries, but will take some older rechargeable AAA NiMH batteries. But so far it has recharged my Eneloops just fine.

So I'm thinking I'll return this and order the Panasonic BQ-CC17 charger instead.

 

[sbslider]

I bought this charger yesterday and today, stumbled across this review which doe NOT recommend the CC55 due to lack of thermal management.
https://www.filterjoe.com/2017/03/11/best-budget-chargers-bqcc55-fct344-bqcc17/

This charger seems pretty finicky about the batteries it will accept too as it won't accept my older rechargeable AA NiMH batteries, but will take some older rechargeable AAA NiMH batteries. But so far it has recharged my Eneloops just fine.

So I'm thinking I'll return this and order the Panasonic BQ-CC17 charger instead.

I am happy with my BQ-CC17. The only time the batteries get warm is near the end of the charge time.

 

[ChibiM]

I bought this charger yesterday and today, stumbled across this review which doe NOT recommend the CC55 due to lack of thermal management.
https://www.filterjoe.com/2017/03/11/best-budget-chargers-bqcc55-fct344-bqcc17/

This charger seems pretty finicky about the batteries it will accept too as it won't accept my older rechargeable AA NiMH batteries, but will take some older rechargeable AAA NiMH batteries. But so far it has recharged my Eneloops just fine.

So I'm thinking I'll return this and order the Panasonic BQ-CC17 charger instead.

I`ve read that test as well.
Although the BQ-CC55 charges at a faster pace, I don`t think it`s a bad charger. It can be finicky with older (non-eneloop) cells especially. That just tells you you better get eneloops
I`ve been told that temperature of 50-55 degrees Celsius is no problem and that the BQ CC55 has a temp cutoff at 57 degrees.
If you dont mind to wait longer for the batteries to finish charging, go for the BQ CC17, otherwise be happy with the BQ CC55.
You could also wait a month or so, and go for the BQ CC65 when it becomes available.

 

[speedlever]

I`ve read that test as well.
Although the BQ-CC55 charges at a faster pace, I don`t think it`s a bad charger. It can be finicky with older (non-eneloop) cells especially. That just tells you you better get eneloops
I`ve been told that temperature of 50-55 degrees Celsius is no problem and that the BQ CC55 has a temp cutoff at 57 degrees.
If you dont mind to wait longer for the batteries to finish charging, go for the BQ CC17, otherwise be happy with the BQ CC55.
You could also wait a month or so, and go for the BQ CC65 when it becomes available.

The only eneloops I have are the gen 1 Sanyo AA and AAA and the gen 4 eneloops that came with the CC55 charger. Yeah, I don't plan to buy anthing but eneloops or their successor going forward.

I didn't realize the BQ-CC65 was only a month out. That could be interesting.

Panasonic is sending me a CC17 to try out. They initially wanted to send me another CC55 but I don't really think anything is wrong with this one. So I'd like to see if the CC17 has issues with my admittedly older rechargeable NiMH batteries. But I confess I was rather stumped when the CC55 red lighted a fully charged AA NiMH battery, but accepted an AAA NiMH battery. Could capacity be a factor?

Do you think that reviewer was over-reacting to the measured battery temp when he said he did not recommend the CC55 because of the temp?

 

[speedlever]

Do you think the BC900 (Rev 33) charger is still ok to use? I'm concerned that it never seemed to stop charging the eneloops (prompting me to buy the CC55 smart charger). I still have a good stash of AA rechargeable NiMH batteries that, at this point, won't charge in the CC55. But I don't want to kill the eneloops if the BC900 doesn't recognize the termination point and overcharges them.

Sounds like my solution is to charge eneloops with the CC55/CC17 and the NiMH batteries with the BC900.

 

[AA Cycler]

Panasonic is sending me a CC17 to try out.

Panasonic BQ-CC17 rejects cells with internal resistance higher than 350mOhm. I guess it will be as finicky with your older AA cells as BQ-CC55.

If you have a use case for high IR cells and still want to use them then I would recommend a charger that does not reject high IR cells, but rather lowers the charge current to prevent overheating. OPUS chargers do that. And also you want to charge high IR cells with low current. For example I charge my high IR cells with OPUS BT-C700 at 200mA.

Cheers,
AA Cycler

 

[ProfJim]

Do you think that reviewer was over-reacting to the measured battery temp when he said he did not recommend the CC55 because of the temp?

I am the author of the Best of the Budget Chargers: BQ-CC55 vs FCT344 vs BQ-CC17 review at the FilterJoe website. The reason the BQ-CC55 charger is not suitable is because when charging two NiMH Low Self Discharge FDKloop batteries (Fujitsu or Panasonic Eneloop) using slots 1 and 2, the maximum battery temperatures went as high as 53o​ - 58o​ (C).

The Fujitsu FCT344 charger's battery temperatures were always 39o​ (C) or lower during all of the two slot tests. I feel that all compact budget battery chargers should require little or no thought given to which slots should be used. The only exception is to decide if you want a high/fast charge rate using only one of two batteries or a lower/slower charge rate using three or four batteries.

In the review I said:

• when charging two low self-discharge AA batteries, they must be inserted in the #1 and #4 slots to avoid over-heating the batteries
• Testing with four older high self-discharge AA batteries with high internal resistance caused the batteries to get too hot to touch but the BQ-CC55 charger did not pause or stop the charging process and temperatures kept rising. It was clear after 5 hours that the charging was unlikely to ever terminate and the temperature seemed dangerously hot so the test was halted.
• The BQ-CC55 battery charger has poor (if any) thermal management features and is potentially dangerous where batteries might melt or it might catch on fire.
• Joe and I are thinking there's a moral to this story: compact chargers and high charge rates do not easily mix. If you want to charge at a high rate, you're better off using one of the larger, more expensive chargers reviewed elsewhere on this site, as these larger chargers simply do a better job of dissipating heat.

 

[HKJ]

The reason the BQ-CC55 charger is not suitable is because when charging two NiMH Low Self Discharge FDKloop batteries (Fujitsu or Panasonic Eneloop) using slots 1 and 2, the maximum battery temperatures went as high as 53o​ - 58o​ (C).

Why do you believe a short time at that temperature is a problem?

 

[ProfJim]

Why do you believe a short time at that temperature is a problem?

Good question. In re-reading my post I should have said that the BQ-CC55 has major thermal problems when testing with older high self-discharge AA batteries and that charging with only two good FDKloop batteries resulted in much higher maximum temperatures than the BQ-CC17 and FCT344 chargers.

In Joe's Best AA Batteries and Chargers: 2016 Update blog, he reported the following Fujitsu FCT344 charger information:

When charging at such high rates, there is a danger that batteries can overheat, so some form of heat detection is needed. This charger has it, and it was in fact triggered every time I attempted to charge some low-quality high self-discharge NiMH batteries I had lying around (6 years old).


In fact, that is a significant drawback of this charger—you don't want to charge 1 or 2 old, low-quality high self-discharge NiMH batteries that have high internal resistance. They will overheat and stop charging in less than 15 minutes. This occurred even with 4 such batteries charging at the lower rate, though they took longer to warm up and trigger the cutoff.


But there's no reason to keep using old NiMH batteries of the high self-discharge variety. I only keep mine around in order to test chargers—I've long ago quit using them in any of our devices.


When I first published this article, I recommended this Fujitsu charger above the Panasonic (BQ-CC17). But I have since changed my mind. Occasionally, the Fujitsu charger refused to charge my older Eneloop batteries that have developed some internal resistance over time and have lower maximum capacity than they used to.


If you're willing to stick with high quality, low self-discharge batteries, occasionally weeding older ones (that have begun to decline in capacity and increase internal resistance), the Fujitsu Quick Charger is still a good choice among budget chargers.

I stand by my statement that the BQ-CC55 has some serious thermal deficiencies. Most of the time the BQ-CC55 thermal performance is close to, but not as good as the FCT344. Which of these chargers would you recommend for non-technical users?

 

[ChrisGarrett]

Good question. In re-reading my post I should have said that the BQ-CC55 has major thermal problems when testing with older high self-discharge AA batteries and that charging with only two good FDKloop batteries resulted in much higher maximum temperatures than the BQ-CC17 and FCT344 chargers.

In Joe's Best AA Batteries and Chargers: 2016 Update blog, he reported the following Fujitsu FCT344 charger information:

I stand by my statement that the BQ-CC55 has some serious thermal deficiencies. Most of the time the BQ-CC55 thermal performance is close to, but not as good as the FCT344. Which of these chargers would you recommend for non-technical users?

So you're ProfJim, who wrote the article on FilterJoe's blog, which is normally penned by FilterJoe, who's currently too busy writing about baseball?

I'm a Dodgers/Marlins' fan, so I get that, but I just want to get the major players straight in my head.

The bottom line is we all should recycle batteries/cells when they wear out and this probably means high internal resistances for all practical purposes.

I have the Maha C9000 and the LaCrosse BC-700 (real battery cooker) and they both reject batteries that have 'arbitrarily' high I.R.s (according to their engineers). Things do get hot with high I.R.s, regardless of whether they're NiMH or Li-Ion.

It's not, per se, the fault of the charger, although a rejection feature like the two above, would be nice.

We need to define how 'high' is high, as well. My Maha rejects at anything over 2.00v, but I've gotten it to charge at 2.09v in the past and I can trick it into charging batteries with ~2.70v 'I.R.s' by inserting and removing them 5-6 times, bringing down the measured I.R. and allowing the charging cycle to start. However, at some point, jerking around with problematic batteries just isn't worth the fuss and into the recycle bin they go.

Good article, though.

Chris

 

[ProfJim]

So you're ProfJim, who wrote the article on FilterJoe's blog, which is normally penned by FilterJoe, who's currently too busy writing about baseball?

I'm a Dodgers/Marlins' fan, so I get that, but I just want to get the major players straight in my head.

[snip]

Good article, though.

Chris

Thanks Chris, it sounds like you're part of the forum welcoming clan.
I live in Fife, Wa. which is about 116 miles south of SilverFox who lives in Bellingham, Wa.

I've never been much of a baseball fan, but as a kid I did get to go to a few games at Fenway Park while Ted Williams was in the twilight of his career. For too many years while I was growing up the Red Sox had a nasty habit of choking every September by repeatedly snatching defeat from the jaws of victory.

For the past several months Joe has posted a compelling true baseball story in his blog. From Joe's introduction:

I discovered this story within a novel-length forum thread of nearly 2000 posts. Detailed posts from Leo's grandfather are supplemented with questions, advice, and insight from many other baseball-savvy participants. The story starts as Leo enters Little League and has not yet ended, as Leo is in the midst of his college baseball career.

I don't watch or follow baseball but reading about Leo's journey is a whole different story. Saying that Leo's story as told by Joe is a compelling read is an understatement!​

The story starts with One Player's Journey from Little League to College Baseball (The Beginning)

This is my third forum post so I think that the rules say that I can now create a forum signature and even be able to create a forum profile.

My "convoy" is quite a bit smaller than yours. I have 4 Rosewill Cree XLamp XP-G R2 "tactical" flashlights and a modest collection of NiMH chargers including a 2011 Maha C-9000, Opus BT-C2000, Opus BT-C2400, Opus BT-C700, Fujitsu FCT344, BQ-CC17, BQ-CC55 and a Maha MH-C204W "battery starter". I have a 4-pack of Powerex 2700 batteries that still work even though this kit sat unused in my camera since 2009. The rest of batteries are all FDKloop LSD batteries where 75% are from Fujitsu and the rest are Eneloops. Joe had loaned me his La Crosse BC1000 for testing but after 2 months it no longer powers up, even though its power supply shows a no-load voltage of 3 volts.

 

[SilverFox]

Hello ProfJim,

Welcome to CPF.

Tom