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Old Oct 3, 2005, 7:19 AM   #11
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Hi Tom,

I fully agree that there are smart chargers that can rapidly charge a battery even within 15 minutes only. These chargers monitor the temperature, voltage current and so on. They do this to prevent excessive heat from developing.

If you are going to charge the battery manually, meaning with constant current source and timer, charging the battery at a rate equivalent to one hour is difficult to control and in most instances overheating (thermal runaway) can occur.

Battery manufacturers recommend normal charge as C10 and quick charge at C4, this means 14 hours and roughly 3.5 hours respectively using the battery Ampacity as the reference. This is normally printed on the battery itself


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Old Oct 3, 2005, 8:20 AM   #12
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Hola Juan!

The "Maha" brand is one of the "Most" reliable chargers/batteries factories, and be 100% sure that what they do...;do it 100% right!

Never any problem with such brand...really I love it!!!

Saludos,

Alex 007
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Old Oct 4, 2005, 1:16 AM   #13
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This is an exerpt from the MAHA website :

page : http://www.mahaenergy.com/store/twowayfaq.asp



Q: Can the NiMH battery pack work with the charger from radio manufacturer?

A1: If you have a slow charger or wall adapter:

Maha NiMH battery packs will work with slow charger/wall adapter, or any charging method with a charging rate less than C/10 or 1/10 of battery capacity. Batteries can be continuously overcharged, at C/10 or lower charge rate. This battery also has chemical built-in reverse polarity protection. Also observe the following while using a wall adapter:

  • If the wall charger / trickle charger goes through the radio, be sure the radio is OFF during the charging.
[/*]
  • If the wall charger goes DIRECTLY to the battery pack, please also administer the following:
[/*]
    • The charge current must be less than 1/10 of the battery capacity. (i.e.: If your battery pack is 1800mAh, then the maximum charge current must not exceed 180mA) [/*]
    • The polarity of the charger connector is the same as labeled on the battery pack casing, or charging socket protective rubber.
[/*]
A2: If you have a rapid charger:

Maha NiMH battery packs will work with compatible rapid chargers, with proper termination. Check if your charger meet any of the termination methods:
  • Temperature Cut-off termination [/*]
  • Negative Delta V termination, with 10-15 mV per cell [/*]
  • Peak Voltage Cut-off
[/*]
If the charger does not meet any of the above termination methods, Maha battery packs are equipped with built-in temperature cut-off termination. Note that once the temperature rise to 55 degree C, charging circuit will be shut-off. BUT after 1-2 hours, the charging circuit will reactivated, after the temperature drops. It is highly recommended that you use a regular slow charger or wall adapter or use a Maha NiMH / NiCD Charging System.



On the last paragaraph regarding overheating, MAHA highly recomends that you use slow charger.


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Old Oct 4, 2005, 1:33 AM   #14
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Hi,

According to the 204F manual, the charging current is 500 mA. This means that if you are charging a 2000 mAH battery, it will take the charger about5 to 7 hours, for 1000 mAH it will take about 3 hours.

If the charger charge the battery in less time than what is expected, it means that the battery capacity is lower than what is indicated.




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Old Oct 4, 2005, 3:55 AM   #15
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Hi Juan!

Really I never check 100% exactly how long my lovely Maha charge my collection of mixed NiCD & NiHA batteries, really Jaun...as a "Pensioner"...I always take my life "Easy" However, seems me that you "Add:? One hour more that needed. What you dob't have time or a few batteries sets?

However if you are "Newer"...on rechargeable batteries types, buy ONLY NiHA...and another "Faster" Maha charger as my son just acquired; this model MH-C204W...ONLY FOR NiHA rechargeables batteries.

Inform us your selection!

Cheers,

Alex 007
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Old Oct 4, 2005, 8:13 AM   #16
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Hello Juandelacruz,

Keep in mind that there are different considerations when charging battery packs. Single cell charging does not have to make allowances for cell to cell conections, nor does it have to consider cell to cell balance.

juandelacruz wrote:
Quote:
Hi,

If the charger charge the battery in less time than what is expected, it means that the battery capacity is lower than what is indicated.




Another meaning could be that the battery was not fully discharge before you re-charged it...

Tom
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Old Oct 4, 2005, 9:46 AM   #17
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Hi!

Just found the only review of ths Maha charger that my son select for his own use! Again...ONLY for NiHA batteries.

http://www.imaging-resource.com/ACCS/C204W/C204WA.HTM

Regards,

Alex 007
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Old Oct 6, 2005, 7:55 AM   #18
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Hi,

We are assuming that we are charging the battery when its empty.

Can you fully charge a 1000 maH battery with a 500mA charger in 1 hour ?

Certainly not, you need at leat 1000 mA or 1 Amp to fully charge the battery in one hour assuming thereare no losses (no losses are impossible to attain), even single cell charging has losses, the intercell connection in battery packs have negligible resistance, the internal resistance is causing all the losses.


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Old Oct 6, 2005, 1:51 PM   #19
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Hi Juandelaceuz!

My in use Maha is the older one C-204F' which accept also NiCD type batteries, this one from my son I wanted only to check up.

I dislike very much so "Rapid' charger; mine as you wrote charge in a much slow rate!

NO my two GP sets 1300 NiMH batteries were NOT completly emptly...however I think that FOR only ONE so fast charge nothing harm will happen to the cells :?

Thank you very much for your cute advice

Regards,

Alex 007:|
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Old Feb 5, 2006, 6:43 PM   #20
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hi,

anyone who has an idea about the compatibility of gp 2500mAh batteries with uniross sprint photo charger + 4x2300mAh batteries bundle? may i charge those 2500mAh batteries with no loss?
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