Maha MH-C401FS vs. Lacrosse BC-900

[Muse]

Which do you prefer and why? [Yup, my first post!]

I realize that the BC-900 gives you a lot more control, but have read a number of posts about the melt-down problems (the thread devoted to it). I wonder how significant that is -- the prospect of a meltdown. Has La Crosse done anything to address the problem? Is v33 firmware a help, a solution or actually no different from v32 as La Crosse support has been asserting?

How good is the Maha, OTOH? Is it considered a candidate in the most bang for the buck prize? Well, what is? I thought it was the BC-900 until I read about the melt-down problems.

 

[Stemlin]

I don't have a lot to say but wanted to bump your topic since no one has responded.

I haven't had the BC-900 long but have been happy with it. Just to be on the safe side I blow a small fan on the charger. Also, you can place some small objects under the charger to raise it a bit and allow for some air to flow underneath. The ability to discharge cells and find out battery capacity is a huge plus, especially in the case of new cells.

The Maha charger claims that it uses special "FLEX NEGATIVE pulse charging" to condition batteries while it charges, which "makes manual conditioning unnecessary". I'm skeptical but maybe others have used this charger and can comment.

 

[Muse]

Thank you. Having read a lot of posts, etc., I have been thinking the same things. Fan, isolate (I like that idea about raising it for better air circulation!) for both cooling and potential fire prevention. Some have said that they keep it on a metal surface or ceramic tiles. I have quite a few questionable cells of various kinds and I know the BC-900 would help a lot in evaluating these and probably bringing a lot of life back to some of them. It would surely be a benefit in pairing them.

 

[coppertrail]

I wouldn't go with the 401FS simply because it "cooks" cells on fast mode, and the charging current on slow mode (300mA) is too low for today's higher capacity NiMH cells (Sanyo 2700 mAh, etc).

In the MH-C9000 manual, Maha recommend a charging rate between .5C and 1C. At 300 mA, you're charging 2700 mAh cells at .1C, thus increasing the potential for missed charge terminations and overcharging.

 

[SilverFox]

Hello Muse,

Welcome to CPF.

Picking a battery charger can be a difficult task. The battery manufacturers suggest fast charging, to insure a strong end of charge signal, at 0.5 - 1.0C. However, there are such a variety of cells available, that it is difficult to pick one charge rate that will work best for all.

Now we are in a compromise situation...

One thought is to pick a charger for each cell capacity that you have...

The 700 mAh AAA cells would need a charge rate in the range of 350 mA - 700 mA.
The 850 mAh AAA cells would need a charge rate in the range of 400 mA - 800 mA.
The 1000 mAh AAA cells would need a charge rate in the range of 500 mA - 1000 mA.

If you have these cells, you could charge all of them if you had an AAA charge rate in the range of 500 mA - 700 mA.

Now, let's move on to AA cells.

The range of AA cells runs from 1200 mAh to 2900 mAh. Let's look at these extremes.

The 1800 mAh AA cell would need a charge rate in the range of 600 mA - 1200 mA.
The 2900 mAh AA cell would need a charge rate in the range of 1450 mA - 2900 mA.

Now we have a problem. There is no overlap. If you have these cells, your charge rate would be 1200 mA, but 1200 mA is a little bit low for the 2900 mAh cells. It may be close enough to work, but you will have to keep track of things when charging your 2900 mAh cells.

A "most bang for the buck" universal charger would be one that charges AAA cells at 500 mA, and AA cells at 1200 mA.

Charging is possible at lower rates, but the end of charge signal determination needs to be adjusted, and the charger may miss the charge termination and have to end the charge based on time.

If you fully discharge your cells every time, you can have a very simple charger that charges at a slow rate and terminates on time. However, it is possible to do damage to your cell if you try to charge it and it is only half empty.

Some of us prefer chargers that have multiple charge rates, so we can adjust the charge rate for the battery we are charging. Some prefer to have the ability to test the batteries to see what condition they are in. Some prefer to have the ability to run the charger off of 12 volts, if needed. Some need batteries right now, others have time for slow charging.

The list goes on... Where do you fit in?

Tom

 

[Muse]

Thanks, Tom. Usually, I'm not in a hurry, only rarely so quick charging is not important to me. If I need a quick charge on AA's I'll just charge up some I have that aren't much depleted without discharging them first. I've never charged a battery in a car and don't anticipated wanting to do that soon. In any case, I do have a charger that came with a car adapter and I could use that in a pinch if I'm careful.

Lately, I decided I want to discharge my NiMH batteries whenever charging them basically because I don't use them all that much. I believe NiMH batteries like to be fully discharged and then charged every month or two, and I don't charge mine more than once a month, for the most part, often a lot less.

I have some presumably 700 mah NiMH AAA's and some 750 mah NiMH AAA's. Some of them are questionable. In fact, a few are probably dead, maybe revivable with the right charger. Even the best seem to only get good capacity with at least 2 full discharge/recharge cycles (every time I recharge them!) with my current Maha 204F charger. I've been using them in a remote, so I figure I'll replace them with some LSD cells for better life. I plan on buying some Rayovac Hybrid AAA's and AA's shortly.

I have a fair number of NiMH AA's, ranging from 1800 mah to 8 Powerex 2300 mah. All but the Powerex are in questionable condition, but they are good for something, some better than others. I think the BC-900 or the Maha C9000 would help me to evaluate, recondition and pair them and cull out the stinkers.

I do have a very old charger that I used to use with my Nicd's that's basically a trickle charger. I think I might be able to use that for the complete discharge/trickle charge scenario. It's so slow that it would probably be no danger for NiMH's. Of course, it would be very slow, but if time is no issue, it's probably an option in tandem with a charger that will discharge the batteries first. This thing is a Burgess and over 20 years old, model 15, rated at .075 amps. I determined a charge rate of 45 ma somehow, maybe calculating, maybe using a multimeter. It has 4 bays accommodating AA, C and D cells, but I adapted it to accept AAA's too. An interesting thing I just realized is that this charger has no ventilation for the batteries. It may not be an issue with the slow charge rate, but in order to function the lid has to be closed. I could modify it to work around that if I want t make sure that air circulates around the cells -- couldn't hurt.

 

[bp044]

How about a compromise ?And all who answer excuse my ignorance.
if one were to use a zts to check cell condition and buy one of the Maha 800 series which seem to have proven reliability , would this not serve for almost all applications especially Eneloops

 

[SilverFox]

Hello Bp,

After giving it careful consideration... I think you should go with the Schulze... :devil:

Tom

 

[bp044]

Hello Bp,

After giving it careful consideration... I think you should go with the Schulze...

Tom

Hello Tom My goal is to simplify my life and the 12 volt power supply and expense of the Schulze doesnt do it. Can you please consider an alternate suggestion or point out the weakness of my previous notion ?

 

[SilverFox]

Hello Bp,

Of course there is nothing wrong with the 800 series chargers, and if you have multi cell applications, the ZTS can help you make sure you are using cells that have the same state of charge.

I was joking and thought I would give you a bad time...

Tom

 

[verge]

bp044, looking at the specs of Maha 800 series chargers the MH-C801D or MH-C808M will do the job based on the recommended charging rate for AA and AAA batteries.

MH-C401FS Battery Charger
Rapid Charge Current: 1000mA (AA), 500mA (AAA)
Slow (Gentle) Charge Current: 300mA (AA), 200mA (AAA)
Trickle Charge: 50mA

MH-C800S
Fast Charge Current: 1000mA (AA), 700mA (AAA)
Soft Charge Current: 500mA (AA), 350mA (AAA)
Conditioning Discharge Current : 250mA

MH-C801D
Fast Charge Current: 2000mA (AA), 700mA (AAA)
Soft Charge Current: 1000mA (AA), 350mA (AAA)
Conditioning Discharge Current : 250mA

MH-C808M
Fast Charge Current: 2000mA (AA), 700mA (AAA)
Soft Charge Current: 1000mA (AA), 350mA (AAA)
Conditioning Discharge Current : 250mA

 

[bp044]

Tom I have nerver heard of you giving anybody a bad time thank you for your tolerence and good advice- verge ditto for yours

 

[Alan_L]

Has there been any reports of meltdowns or missed termination signals with the 401FS on slow mode? In theory the rate should be too low for high capacity batteries, but I haven't read anything negative about this charger. I'm not saying it hasn't happened, but I just might have missed it.

Alan

 

[jusko]

I have yet to see a missed termination with the 401FS on slow or fast mode. I would say it is the most reliable and stable one among Maha's chargers. It accepts 'crap' cells that refused by the C9000. Its not affected by a fan blowing across the charging cells, so no cooking of cells occurs.

jusko

 

[SilverFox]

Hello Alan,

The only charger that I am aware of that has melted down is the BC-900. Some other chargers have gotten cells hot enough to deform the plastic of the charger, but the charger did not melt down.

I can almost understand and forgive a charger that destroys cells, but there should not be any incidents of a charger melting down. There are several layers of safeties built into most chargers to prevent this from happening.

There may be other chargers that have melted down, but I am not aware of them. The LaCrosse BC-900 holds the record for this.

In all fairness, there have been very few melt downs since the release of V33, and my V32 has been working fine for about 2 years now. However, I still use it cautiously and expect it to melt down, taking precautions to make sure any mishap is contained.

The Maha 401 just seems to get some cells hot when charging at the fast rate. This is a whole different issue.

Tom