LaCrosse BC-9009 / BC-900 - The Melt-Downs Continue...

[Bones]

It seemed, at least for a while, that LaCrosse had largely rectified the melt-down problem with their Alpha-Power charger.

However, after noting the reports in the following thread of at least two melt-downs of their latest model, the BC-9009 with the v.35 firmware update, I perused the most recent reviews at Amazon and found what appears to be a significant increase in the number of melt-downs or near melt-downs in the past couple of months:

http://www.candlepowerforums.com ... post3190563

From Amazon

Dated 12 Jan 2010:

Worked fine for two weeks, then melted, January 12, 2010, by Michael Stratton

Yes, another melted BC-9009. It worked great when I first received it. Probably charged or refreshed six or eight sets of batteries. Then when I was running a refresh cycle (discharge 500 mA, charge 1000 mA) on the included AA batteries it self destructed. Smell of burning plastic, the LCD for the third slot turned completely black and three of the buttons sank into the charger (probably melted inside).

Just glad I was at home and could unplug the unit before something caught fire. Obviously there is a quality issue, as many others have reported the same problems. For a time Amazon had pulled availability of the BC-9009, but I see it is for sale from Amazon once again.

I sent mine back for a refund. My advice would be to stay away.

More...

Dated 10 Jan 2010:

http://www.amazon.com/review/R248CZUT53D5WN/

Dated 10 Jan 2010:

http://www.amazon.com/review/R27WJD0EA1O7R3/

Dated 07 Jan 2010:

http://www.amazon.com/review/R2PN0S7VHR69AF/

Dated 05 Jan 2010 (2 Incidences):

http://www.amazon.com/review/R16BT9REEO5QY7/

Dated 05 Jan 2010 (2 Incidences):

http://www.amazon.com/review/R2S413NI95BGC2/

Dated 03 Jan 2010:

http://www.amazon.com/review/RSD32V53429SF/

Dated 02 Jan 2010:

http://www.amazon.com/review/RG4AOAUZ7UTJC/

Dated 29 Dec 2009:

http://www.amazon.com/review/R19FBYZU542MOK/

Dated 28 Dec 2009:

http://www.amazon.com/review/R34FWSW8QGBRBY/

Dated 26 Dec 2009:

http://www.amazon.com/review/R1NM3UBA91JIAD/

Dated 25 Dec 2009:

http://www.amazon.com/review/R2KH46D7NR3XY6/

Dated 24 Dec 2009:

htttp://www.amazon.com/review/R265JWP92XFQZI/

Dated 22 Dec 2009:

http://www.amazon.com/MsgID=Mx2OD10ZT5ERISW

Dated 22 Dec 2009 (2 Incidences):

http://www.amazon.com/review/R2WE84Q2TEP8TI/

Dated 19 Dec 2009 (2 Incidences):

http://www.amazon.com/review/R15CP9DB5DASPI/

Dated 15 Dec 2009:

http://www.amazon.com/MsgID=Mx2FSQ3IYXHPOO1

Dated 14 Dec 2009:

http://www.amazon.com/MsgID=Mx3MROLMCWQVV1K

Dated 08 Dec 2009:

http://www.amazon.com/review/RFWRPZDNWN5RI/

Dated 04 Dec 2009:

http://www.amazon.com/review/R2BRM2XYRS8NYT/

Dated 22 Nov 2009:

http://www.amazon.com/review/RK9Z23QEJZ2BW/

Dated 15 Nov 2009:

http://www.amazon.com/review/R1QVSR3EN62LT3/

Dated 05 Nov 2009 (2 Incidences):

http://www.amazon.com/review/RDRC22JHJ9SO2/

Dated 03 Nov 2009:

http://www.amazon.com/review/RPX2WEKP5IHRO/

Dated 29 Oct 2009:

http://www.amazon.com/review/R1STOB1Y6JNRT8/

From CandlePowerForums

Dated 12 Jan 2010:

...

I got it from Amazon Dec, 2009. It came with 4 AA, and 4 AAA batteries. I put the 2600 mAh AA batteries in, plugged it into an empty outlet and left the house for a couple hours. When I returned, the charger was smoking hot, as were the 2 center batteries, the display above the batteries was black, and the 2 middle buttons in the row of 4, were melted and had dropped down. I let it cool, and tried it again, and it still seems to work, but it is going back to Amazon pronto. I am lucky to still have a house.
.

Dated 07 Jan 2010:

http://www.candlepowerforums.com ... post3228150

Dated 02 Jan 2010 (Voltcraft IPC-1)

http://www.candlepowerforums.com ... post3222370

Dated 26 Dec 2009:

http://www.candlepowerforums.com ... post3214310

Dated 11 Nov 2009:

http://www.candlepowerforums.com ... post3165721

http://www.candlepowerforums.com ... post3168416

Anyway, something to keep in mind when choosing a location to operate any charger, and especially the Alpha-Power.

One Possible Cause

Insofar as the cause of the melt-downs is concerned, this speculative post by William Chueh seems the most plausible to me:

Hello folks,

Can't say I am an expert on the BC-900, but judging from the photos posted I believe the problem was not due to a "missed termination."

In the BC-900 design, it uses a very small package MOSFET (SOT23) as a linear step-down regulator which has to disspate power due to the difference in voltage between the power supply (4V) and the battery (1.5V). The power disspated by the MOSFET is the current times the voltage difference. At peak charging current, the wattage disspated is considerable.

This is not a typical design as most chargers today use a "switching buck design" which uses a inductor, transistor, diode and capacitor to convert the voltage. This design usually gives 70-80% conversion efficiency even at a large voltage difference, but it's more expensive to make.

Back to the point, I believe it is possible that the MOSFET failed due to either a surge in the Gate-to-Source voltage causing the gate oxide to break. Even more likely it is due to the aging of the MOSFET since it is taking a huge toll close or beyond its power disspation limit. As a result, the probability of MOSFET failure increases.

When a MOSFET fails, it can either become always OPEN or always SHORTED. In the latter case, there would no longer be a current limiting component between the charger and the power supply causing the all the current to rush to the batteries. Furthermore, since the MOSFET is always SHORTED there's no way to stop the charging even if the microcontrolluer unit sends the signal to stop the current. Therefore, it doesn't matter if there is a thermocouple or voltage-based termination, since the MCU is no longer able to control the charging current.

Just my two cents.

William

A Final Note

I've scoured the web for reports of the less powerful LaCrosse BC-700 melting down, and have yet to locate even one...

 

[Lightcrazycanuck]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...



This thread is better than reality TV.:thumbsup:


lovecpflovecpflovecpf

 

[MarioJP]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

Ok Now I am starting to really get suspicious about this now. Or am i the lucky one that have 2 of these exact same charger that i have no problems so far.

I am curious what triggers this to happen I am at a lost here. Either I am lost or gotta take the amazon reviews with a grain a salt. I have done refresh/test cycles, left it overnight, had cells overheated, used every current charge settings that this charger offers. And above that I been using this charger constantly or being put to heavy use. I have not had a meltdown despite of this. Have this charger for 3 months or so. Unless it takes many month to a year before you start to see problems?? I dont know.

 

[Mr Happy]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

How can I explain this to you? It is not normal behavior, it is a fault. It does not happen to every charger all the time, it happens to perhaps one charger in a hundred, or 1 in 1000. Your chargers may never develop the fault and may never do anything bad. If one person has a car that breaks down, does it mean that every car of that kind is going to break down?

 

[Bones]

.....

 

[alfreddajero]

Didnt know that this was still going on with the charger. I did a lot of searching between this charger and of course the Maha. What i wanted was a charger at a good price and one that was reliable, with the Lacrosse i was intrigued by the batteries that came with the charger and that would mean extra batts for me. But then i noticed a lot of threads on the charger melting etc.....and that really turned me off. I have had my 2 C9000's for a year now and there still charging what i throw at it. I showed my wife the pics of the melted chargers and the wrappers coming off the batts and she was like oh hell no.

 

[TakeTheActive]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

Ok Now I am starting to really get suspicious about this now...

...I am curious what triggers this to happen...

Try this:

1. Plug an 1800 Watt Electric Space Heater into the bottom plug of a dual outlet.
   .
2. Insert 2 FULLY DISCHARGED AA cells into Slots 1 & 4 of your BC-900.
   .
3. Plug the BC-900 into the top plug the same dual outlet as the 1800 Watt Electric Space Heater.
   .
4. Set the BC-900 Charge Current to 1800mA.
   .
5. Turn the 1800 Watt Electric Space Heater ON-and-OFF-and-ON *QUICKLY* and *REPEATEDLY* (to create voltage spikes on that line).

See if your BC-900:

• Locks Up
  .
• Overheats
  .
• Melts down
  .
• Bursts into flames

Disclaimer: *ALL* of the above was intended in jest. :wave:

P.S. Re-read all of Mr Happy's (non-confrontational / informative) posts above. :sigh:

P.P.S. CLICK on my Sig Line LINK and read all of the Keyword: Theory LINKs.

 

[MarioJP]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

Try this:

1. Plug an 1800 Watt Electric Space Heater into the bottom plug of a dual outlet.
   .
2. Insert 2 FULLY DISCHARGED AA cells into Slots 1 & 4 of your BC-900.
   .
3. Plug the BC-900 into the top plug the same dual outlet as the 1800 Watt Electric Space Heater.
   .
4. Set the BC-900 Charge Current to 1800mA.
   .
5. Turn the 1800 Watt Electric Space Heater ON-and-OFF-and-ON *QUICKLY* and *REPEATEDLY* (to create voltage spikes on that line).

See if your BC-900:

• Locks Up
  .
• Overheats
  .
• Melts down
  .
• Bursts into flames

Disclaimer: *ALL* of the above was intended in jest. :wave:

P.S. Re-read all of Mr Happy's (non-confrontational / informative) posts above. :sigh:

P.P.S. CLICK on my Sig Line LINK and read all of the Keyword: Theory LINKs.

Now that's funny LOL.

In any case this is a tough case to solve. Like i said before I have 2 of these same chargers so I can charge 8 cells at a time either one of them has not melted and sometimes leave it overnight if I have to. But most of the time it is only used during the day.

Though I will say that the jack on the back of the charger I did cleaned it a bit and also the barrel connector of the adapter as it was having connectivity problems. I found that out by 2 things.

1. The readings mA charge the numbers would slightly jump around. Like for example If it was charging at 1A. The readings should be constant at 1000 during charging. In my case It would start jumping around. It would go from 1000 to 932 and back and if the numbers jumps too much the charger would sometimes reset itself.

2.One time I came back and it was charging at 200ma even though I have set it to 1A. That's when i knew the charger has reset itself, which is why I decided to clean it.

After I did some cleaning on the jack (back of the charger),and the barrel, and also the battery contacts I never had that problem show up again.

It did that on both chargers too.

 

[PeAK]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

How can I explain this to you? It is not normal behavior, it is a fault. It does not happen to every charger all the time, it happens to perhaps one charger in a hundred, or 1 in 1000. Your chargers may never develop the fault and may never do anything bad. If one person has a car that breaks down, does it mean that every car of that kind is going to break down?

I hope this is not out of context with Mario, but...

I'm sure that both Dell and Sony did not have you representing their case for their defective Lithium-Ion batteries found in a few of their exploding laptops. There were 16 incidents out of 3 million batteries sold that prompted a wide scale recall...I think the Lacrosse defect rate is presently a "bit higher"...
​

This said, there is a competing product known to all CPFers that has yet to exhibit the same problem. Your mileage may vary.

 

[Mr Happy]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

I hope this is not out of context with Mario, but...

I'm sure that both Dell and Sony did not have you representing their case for their defective Lithium-Ion batteries found in a few of their exploding laptops. There were 16 incidents out of 3 million batteries sold that prompted a wide scale recall...I think the Lacrosse defect rate is presently a "bit higher"...
​

Sure, I know

It's just that Mario seemed to keep asking why his units have never had a problem, and how could that be?

 

[damn_hammer]

i checked on the consumer product safety website, and couldn't find a any reports on the la crosse charger. obviously people are having problems, it's just odd to me why it wouldn't have been reported if this was a significant hazard.

 

[Bones]

...
In the BC-900 design, it uses a very small package MOSFET (SOT23) as a linear step-down regulator which has to disspate power due to the difference in voltage between the power supply (4V) and the battery (1.5V). The power disspated by the MOSFET is the current times the voltage difference. At peak charging current, the wattage disspated is considerable.

...

When a MOSFET fails, it can either become always OPEN or always SHORTED. In the latter case, there would no longer be a current limiting component between the charger and the power supply causing the all the current to rush to the batteries. Furthermore, since the MOSFET is always SHORTED there's no way to stop the charging even if the microcontrolluer unit sends the signal to stop the current. Therefore, it doesn't matter if there is a thermocouple or voltage-based termination, since the MCU is no longer able to control the charging current.
...

Would it be reasonable to presume that if the MOFSET fails in the shorted position, the result would be equivalent to connecting the power supply directly to the cells in parallel circuit?

 

[moldyoldy]

fyi: to provide a standard engineering support for Mr. Chueh's reasonable speculation on a possible root cause of meltdowns in the BC-900 chargers. Note that a specific failure may be due to voltage spike or just about anything. The root cause is usually HEAT (excessive) which is nearly always the enemy of electronics! less the old tube systems where the coated cathode had to be heated to glowing to emit. <am I showing my age?>

It is standard electrical engineering design practice to rate any heat dissipating device at 1/2 of spec before implementing. ie: a 1/2 watt resistor shall not be implemented in a design at more than 1/4 watt. Ditto for active devices such as transistors and MOSFETs. Ditto for voltage ratings as well. If the mains power is "120VAC", thou shall not employ any diode with a rating less than a 400PIV, minimally it should be rated at 600PIV, and preferably rated at 1000PIV. PIV = Peak Inverse Voltage. This is historically a reliable recommendation, but it does force usage of more expensive components which raises the cost of the product.

Switching to a product level, the US Navy has recorded that most fleet failures are due to power supplies. If you review the specs for power supplies where ratings are provided for % of rated current vs expected lifespan, the numbers again reinforce the recommendation of not using any device at full rating which simply ensures a short operational life. Selecting a device at 1/2 of rated specification is still the recommendation.

To the case of the LaCrosse BC-900 & BC-700 units. As was observed before on CPF, I also have not read any case on the Internet of a BC-700 unit having "melting" problems. Note that the BC-700 is limited to a 700ma charge rate. I myself have had no failures of any kind in 2x BC-900 or 2x BC-700 chargers, nor do I believe that I have ever come close - and I do check! In a test, I have observed a charge cessation due to excessive cell temperature on the BC-900 v33 when 4 AA cells were being charged at 1000ma. Charging 4 AA cells at 1000ma is very much NOT recommended in the BC-900 except for short bursts, but certainly not from low voltage to cutoff!

As for the BC-900 unit, charging at the full rating of 1000ma for 4 cells will not only heat up the cells, but heat up the charger...excessively in my opinion. Mr Chueh's observations are completely consistent with the engineering doctrine of excessive heat kills electronics.

By comparison, the Maha C9000 charges AA cells by default at 1000ma, but there is plenty of room between the cells and the charger itself has a bail to prop up the back end. The point is to avoid excessive heating, or operation at top heat, will eventually kill any power device.

Recommendations? Regardless of the charge recommendations for the batteries, I rarely use more than 500ma charge rate in any of the BC-900 or BC-700 chargers. I also keep them plugged in to some sort of a good surge suppresor. I also keep the back end of the charger propped up with an eraser or anything to give the charger at least a cm or 1/2".

To further make the point: I have deployed several Maha 9V smart chargers. Those devices have also experienced "hard" failures - non-operational. I was not around when they failed. However upon disassembly, 100% of the time, those failures were in the power-handling IC. 'nuff said.

a MoldyOldy.

 

[Lightcrazycanuck]

Thanks Moldy for your report and observations.:thumbsup::thumbsup::thumbsup:

Being in R/C for the past 25 years I can also agree to the fact that HEAT KILLS electronics!

Or crashs from high Alt.

My #1 concern when charging batteries of any chemistry is how hot the battery is getting.I keep a very close eye on the charging process and never ever leave it unattended.For double insurance I use a LiPo sack.

 

[damn_hammer]

i understand the conditioning cycle to take many hours to days? to complete. i'm not sure of the exact terminology as i own the bc-9009 but have not taken it out of the box yet. that's dedication to never let it out of your site that whole time.

 

[KiwiMark]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

I have not had a meltdown despite of this. Have this charger for 3 months or so. Unless it takes many month to a year before you start to see problems?? I dont know.

I also have 2 of these and the newer one is now over 1 year old, the older one is 4 & 1/2 years old. I have yet to experience a problem with either charger. I am sure that most sold never fail.

 

[Bones]

i checked on the consumer product safety website, and couldn't find a any reports on the la crosse charger. obviously people are having problems, it's just odd to me why it wouldn't have been reported if this was a significant hazard.

These melt-downs have, thus far, seemed to be fairly benign in that they've only seriously damaged the charger and cells and, in some instances, whatever the charger is resting upon.

However, given my presumption that if the MOFSET fails in the shorted position, then the full output of the 4 volt power supply will be pumped directly through circuits not designed to take that much voltage or current into a small 1.2 volt cell, the potential is certainly there for a more tragic outcome. Perhaps prompted by nothing more than a tissue inadvertently dropped by a child or the chemical impurities in a sub-standard cell reacting much more violently to being connected directly to the power supply than those in the trusty Eneloop.

 

[lrp]

I've used mine, older model, for years and have experienced no problems whatsoever and totally agree with Mr. Happy!!

 

[Bones]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

I also have 2 of these and the newer one is now over 1 year old, the older one is 4 & 1/2 years old. I have yet to experience a problem with either charger. I am sure that most sold never fail.

Even though I've seen it a few times now, the last sentence in your signature line still prompts a chuckle.

Thanks.

 

[KiwiMark]

Re: LaCrosse BC-9009 / BC-900 - The Melt-downs Continue...

Even though I've seen it a few times now, the last sentence in your signature line still prompts a chuckle.

I even managed to use that line in real life, after pulling out the third light someone asked "are you afraid of the dark" and I instantly remembered something that I had read once on these forums, so I said "no, the dark is afraid of me!".

The funny thing is that I didn't even have my bright lights with me, I only had a ROP High as my brightest. My 150W and 180W hotwires were at home and I hadn't finished my 216W beast at that time. Now my brightest 3 are 80W, 180W & 216W incans, then I have my 2 3854 ROP Highs, 3853 ROP High and 3854 ROP Low plus a bunch of bright LEDs.

I think non-flashaholics just don't get why we have so many lights. Most people would not understand why I have so many chargers either - I should get rid of some of the ones that I no longer use. I currently use as required: 2 Hobby chargers, 2 LaCrosse BC-900 chargers & 2 WF-139 chargers (plus proprietary chargers for my Camera, cell phone, shaver & toothbrush). I have another half dozen or so chargers that I don't use. I have a lot of rechargeable batteries too - NiCd, NiMH, LiCo, LiMn & LiFePO4 chemistries in AAA, AA, D, 10440, 14500, 16340, 16850, 26500 & 32600 sizes. Now I'm building a collection of knives as well.