have both BC-900 and C9000 and confused

Turbo V6 Camaro

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I have been reading here for a while.

I have the bc-900 and C-9000 I like them both for different reasons.

but it i use the refresh cycle on the bc-900 I get 2650 out of my powerex 2700 batteries at

350 discharge and 700 charge.

1. on the c-9000 the same exact cells read only ~2500 :sick: (witch i realize is in the range)

2. now i just read in another thread to charge and .5c (the c-9000 says .3-1c) so why does the break cycle charge/discharge so slow?

3. the bc-900 DOES not support that unless only 2 battery are done. should i get another C-9000?

I have
eneloop - 2000 (test at 2100 i nthe bc-900 and only 1800 in the c-9000)
imedion -2100 (testing now)
energizer - 2450 (cycleing on the bc-900 now)
la crosse - 2600 ( came in at 2600 on the bc-900)

4. energizers, should i cycle them at 1300/700 first or what? (they are older cells charged by a 15 hour 150ma charger before i knew about better chargers.

thanks for the advicelovecpf
 

SilverFox

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Hello Turbo V6 Camaro,

Welcome to CPF.

When you ran the test on your cells with the C9000 did you charge at 700 mA, wait 2 hours for the top off charge to complete, then run the discharge at 350 mA? Oops, you can't discharge at 350 mA on the C9000, so select 300 mA.

Run this test and see if it comes close to what you get with the BC-900. Be sure to start the discharge immediately after the 2 hour top off. If you wait longer, your results will be lower.

The Break-In function is a special case that is designed to get the most out of the cell, and to condition it for use. The charge termination is done with a time limit, and the charge rate is low enough to minimize the damage done by overcharging.

Normal charging often is terminated by the drop in voltage that occurs as the cell reaches full charge. That signal is strongest when the cell is charged at a rate in the 0.5 - 1.0C range. To minimize the possibility of overcharging, it is good to charge at a rate that produces a strong end of charge signal.

As far as your various cells go, the best thing to do is to discharge them, then run a Break-In cycle on them in the C9000. This will give you an idea of how they are doing. If they end up with capacities below 80% of their initial capacity, the have crapped out and should be recycled.

Tom
 

Turbo V6 Camaro

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Hello Turbo V6 Camaro,

Welcome to CPF.

When you ran the test on your cells with the C9000 did you charge at 700 mA, wait 2 hours for the top off charge to complete, then run the discharge at 350 mA? Oops, you can't discharge at 350 mA on the C9000, so select 300 mA.

Run this test and see if it comes close to what you get with the BC-900. Be sure to start the discharge immediately after the 2 hour top off. If you wait longer, your results will be lower.

The Break-In function is a special case that is designed to get the most out of the cell, and to condition it for use. The charge termination is done with a time limit, and the charge rate is low enough to minimize the damage done by overcharging.

Normal charging often is terminated by the drop in voltage that occurs as the cell reaches full charge. That signal is strongest when the cell is charged at a rate in the 0.5 - 1.0C range. To minimize the possibility of overcharging, it is good to charge at a rate that produces a strong end of charge signal.

As far as your various cells go, the best thing to do is to discharge them, then run a Break-In cycle on them in the C9000. This will give you an idea of how they are doing. If they end up with capacities below 80% of their initial capacity, the have crapped out and should be recycled.

Tom
ahh i was just using the cycle functions in the c-9000 did 4 cycles and those where the number i took.

I seen the top off is not run during the rest poid then.

So it better to charge the cells at .5c then let them top off. rather then charge at 200 (like the bc-900 defaults too) for like 3/4 of a day :rolleyes:

i'll charge the 2000 cells in the bc-900 and the others in the maha 900

thanks :)
 

VidPro

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actually there is no 200ma charge rate :mecry: on the LaCross, its Averaged 200, it is actually 1000ma being pulsed, i mention that because 1000ma is NOT a within spec slow overcharge rate, even though most stuff can handle it.
That could be a very important difference between thinking that we are doing a nice slow overcharge rate, while instead it is pounding the cell at an overcharge rate that is well beyond the specs for the cell. i dont see the specs saying you can "overcharge" it at .5C in AVERAGED pulses, like these type of chargers can do. so when it comes to slow overcharge its REAL .1C or it Isnt, and I make that distinction even if the chargers dont.

so if your trying to "slow" charge "topping" with a PWM type high rate smart charger it simply cant be done. that is why I (myself) would not recommend topping on a la cross 900 Like That specifically.
and without proper termination occuring (sometimes it does sometimes it doesn't) at 200ma, the rate for overcharge is over spec.

from what i read, the 9000 does not discharge as low (so discharge test doesnt take the batt All the way down) , and the 9000 also is nicer on the batteries using the mahas high tech charging alogrythm (like peak voltage), so the batteries are not hurt so much as they would be on the LaCross doing the same thing. so in reality it may not charge to 103% (so to speak) but should treat the cells a lot nicer, and provide with hundreds more cycles, sort-of like a great li-ion alogrythm would.
 
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Turbo V6 Camaro

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actually there is no 200ma charge rate :mecry: on the LaCross, its Averaged 200, it is actually 1000ma being pulsed, i mention that because 1000ma is NOT a within spec slow overcharge rate, even though most stuff can handle it.
That could be a very important difference between thinking that we are doing a nice slow overcharge rate, while instead it is pounding the cell at an overcharge rate that is well beyond the specs for the cell. i dont see the specs saying you can "overcharge" it at .5C in AVERAGED pulses, like these type of chargers can do. so when it comes to slow overcharge its REAL .1C or it Isnt, and I make that distinction even if the chargers dont.

so if your trying to "slow" charge "topping" with a PWM type high rate smart charger it simply cant be done. that is why I (myself) would not recommend topping on a la cross 900 Like That specifically.
and without proper termination occuring (sometimes it does sometimes it doesn't) at 200ma, the rate for overcharge is over spec.

from what i read, the 9000 does not discharge as low (so discharge test doesnt take the batt All the way down) , and the 9000 also is nicer on the batteries using the mahas high tech charging alogrythm (like peak voltage), so the batteries are not hurt so much as they would be on the LaCross doing the same thing. so in reality it may not charge to 103% (so to speak) but should treat the cells a lot nicer, and provide with hundreds more cycles, sort-of like a great li-ion alogrythm would.

i notice that to, the bc-900 goes donw to about .95v the flips over to charge

the c-9000 goes to 1.1v then flips over to rest
 

Mike abcd

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actually there is no 200ma charge rate :mecry: on the LaCross, its Averaged 200, it is actually 1000ma being pulsed, i mention that because 1000ma is NOT a within spec slow overcharge rate, even though most stuff can handle it.
That could be a very important difference between thinking that we are doing a nice slow overcharge rate, while instead it is pounding the cell at an overcharge rate that is well beyond the specs for the cell. i dont see the specs saying you can "overcharge" it at .5C in AVERAGED pulses, like these type of chargers can do. so when it comes to slow overcharge its REAL .1C or it Isnt, and I make that distinction even if the chargers dont.

so if your trying to "slow" charge "topping" with a PWM type high rate smart charger it simply cant be done. that is why I (myself) would not recommend topping on a la cross 900 Like That specifically.
and without proper termination occuring (sometimes it does sometimes it doesn't) at 200ma, the rate for overcharge is over spec.

...

Doesn't every consumer NiMH charger with a user selectable charging current work the same way? Every one I've seen including the early version of the C-9000 I tested used PWM of the full charge rate to provide the lower charging rates.

I share your concern of the higher pulsed rates but every NiMH and LiOn charger I know of with "soft" (not selector switch) user selectable charge rates uses that method.
 

VidPro

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they do NOW :) it used to be an analog world, now its a digital world.
many things are being done digitally to Mimic analog, and they dont come anywhere close.
now i am not an old foogie stuck in the past, but if your going to complicate things and have all this extra work and effort and high tech stuff, seems it should be Better :)

the main point i would try and make is if you want REAL slow charging, you want REAL slow charge, not a fake version of it digitally reproduced that destroys cells.
so even if it is digital, get a digital that has low current to do any REAL slow topping.

everything has Changed so much in charging, via digital, that the specs arent the "same" , because the specs arent REAL.
if we dont understand all the changes and how were being tricked with cheap digital tricks, then the wrong descisions are being made.

on the other hand Pulse charging is great, so i am not knocking the pulse.

EX: if you cant slow charge with it, then DONT, because it isnt and it cant. <--- and that is the "new" information.
and that is what we have come to, the "facts" are changed even though the specs are the same, because you cant even DO what used to be done.

So a person saying "you slow charge Ni-?? cells at .1c" cant reliably make that statement anymore, and people cant reliably DO that anymore unless they know what the actual Rate IS.

and it is also likly to be why MAHA chose to include thier voltage peaking into the chargers, it can compensate for digital pulverising

analog vs digital again - PWM led driving, totally not the same, and in reality it should not be even called by a specific current rate without the word "Averaged" tossed in somewhere.
again completly worlds apart from each other both electrically and in reality. The real truth , or the inclusion of the word averaging, is just Left Off, like it is inconsequential. Besides it being a lesser way of driving the led, it is the blind lack of even recognising it anymore, it just dissapears with wooden toys :)
 
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TakeTheActive

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...I have the bc-900 and C-9000 I like them both for different reasons.

but it i use the refresh cycle on the bc-900 I get 2650 out of my powerex 2700 batteries at 350 discharge and 700 charge.

...on the c-9000 the same exact cells read only ~2500 :sick: (witch i realize is in the range)...

...eneloop - 2000 (test at 2100 i nthe bc-900 and only 1800 in the c-9000)...
  1. Surface Charge (false higher reading) on the BC-900.
  2. Different DISCHARGE currents
    (Higher DISCHARGE current yields lower CAPACITY as cell's INTERNAL RESISTANCE increases; see IMPEDANCE CHECK below)

...energizer - 2450 (cycleing on the bc-900 now)...

...energizers, should i cycle them at 1300/700 first or what? (they are older cells charged by a 15 hour 150ma charger before i knew about better chargers...
  • DISCHARGE them @ 100mA on the C9000.
  • Post the voltage from an IMPEDANCE CHECK on the C9000:
    Individually, in Slot #4 (with all other slots empty):
Then we can determine the next step (i.e. Years of '15 hours @ 150mA' = large crystals?)...
 

TakeTheActive

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...When you ran the test on your cells with the C9000 did you charge at 700 mA, wait 2 hours for the top off charge to complete, then run the discharge at 350 mA? ...
Did you EVER own and/or use a La Crosse BC-700/BC-900/BC-9009? :eek:oo: :eek: :green: :faint: :eek: :rolleyes:

Anyone who has, for even a short amount of time, recognizes the number combinations:
  • 200/100
  • 500/250
  • 700/350
  • 1000/500
:oops: :crackup:

...Oops, you can't discharge at 350 mA on the C9000, so select 300 mA...
:poke: :wave: :D

Sorry, I saw you 'joke around / poke fun' recently in another thread and just couldn't resist 'poking back' myself tonight! :tinfoil: :buddies:
 

Turbo V6 Camaro

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Click on my Sig Line LINK and read the threads about:
  • Theory
  • La Crosse BC-900
  • Maha MH-C9000
That should answer most, if not all, of your questions. ;)

  1. Surface Charge (false higher reading) on the BC-900.
  2. Different DISCHARGE currents
    (Higher DISCHARGE current yields lower CAPACITY as cell's INTERNAL RESISTANCE increases; see IMPEDANCE CHECK below)

  • DISCHARGE them @ 100mA on the C9000.
  • Post the voltage from an IMPEDANCE CHECK on the C9000:
    Individually, in Slot #4 (with all other slots empty):
Then we can determine the next step (i.e. Years of '15 hours @ 150mA' = large crystals?)...
wow thanks a ton i'll be reading for a while

oh on charger let say i just need to top off because they have been sitting for 5 days, should i still charge at .5C :shrug:
 

TakeTheActive

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...I have the bc-900 and C-9000 I like them both for different reasons...
Me too! :)
  • 2006 Dec: La Crosse BC-900
  • 2009 Jan: Maha MH-C9000
AFAICT:
  • The Maha MH-C9000 is best for NEW, vibrant AA cells.
    (Except for AAAs in BREAK-IN mode - because of the constant '100mA for 2 hours' topoff, use caution when selecting the charging current for AAA cells in the other modes.)
    .
  • The La Crosse BC-900/BC-9009 is best for OLDER, neglected, high resistance, aka *CRAP* AA cells and all AAA cells.
    .
  • The La Crosse BC-700 is *ONLY* best for AAA cells.
    (It cannot charge at 0.5-1.0C for currently available AA cells.)
 

Turbo DV8

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Did you EVER own and/or use a La Crosse BC-700/BC-900/BC-9009? :eek:oo: :eek: :green: :faint: :eek: :rolleyes:


Anyone who has, for even a short amount of time, recognizes the number combinations:
  • 200/100
  • 500/250
  • 700/350
  • 1000/500
:oops: :crackup:


How does this disagree with Silverfox's comment, taken in it's entire context?:thinking:
 

Turbo V6 Camaro

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Me too! :)
  • 2006 Dec: La Crosse BC-900
  • 2009 Jan: Maha MH-C9000
AFAICT:
  • The Maha MH-C9000 is best for NEW, vibrant AA cells.
    (Except for AAAs in BREAK-IN mode - because of the constant '100mA for 2 hours' topoff, use caution when selecting the charging current for AAA cells in the other modes.)
    .
  • The La Crosse BC-900/BC-9009 is best for OLDER, neglected, high resistance, aka *CRAP* AA cells and all AAA cells.
    .
  • The La Crosse BC-700 is *ONLY* best for AAA cells.
    (It cannot charge at 0.5-1.0C for currently available AA cells.)


thanks for all the help heres my contribution, probly repeat info tho

https://www.candlepowerforums.com/posts/3065988#post3065988
 

TakeTheActive

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How does this disagree with Silverfox's comment, taken in it's entire context?:thinking:
Hmmm...

2nd reply tonight where *YOU*, IMHO, over-reacted.

Viewing my *ENTIRE* post:


==========
...When you ran the test on your cells with the C9000 did you charge at 700 mA, wait 2 hours for the top off charge to complete, then run the discharge at 350 mA? ...
Did you EVER own and/or use a La Crosse BC-700/BC-900/BC-9009? :eek:oo: :eek: :green: :faint: :eek: :rolleyes:

Anyone who has, for even a short amount of time, recognizes the number combinations:
  • 200/100
  • 500/250
  • 700/350
  • 1000/500
:oops: :crackup:

...Oops, you can't discharge at 350 mA on the C9000, so select 300 mA...
:poke: :wave: :D

Sorry, I saw you 'joke around / poke fun' recently in another thread and just couldn't resist 'poking back' myself tonight! :tinfoil: :buddies:
[/HR]==========
I don't understand how you missed the 'joke around / poke fun' comment - maybe because it was in 'SIZE=1'? :confused: ;)
 
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