Battery 101 -------------->>>>>
#76
Tech Apprentice
Originally posted by unknown
What if I get a 1800 mAh pack. Will that offer me less run time...? Or less power?
What if I get a 1800 mAh pack. Will that offer me less run time...? Or less power?
#77
Re: Re: Charge times
Originally posted by marvi
im not sure if this is the correct formula but here goes:
charge time (in seconds) divided by 3600. then multiply by the amp rate
for example, charge time is 1500 seconds and rate is 6 amps.
1500/3600 = .4167
.4167 x 6000 = 2500mah
i think this is the same value shown in the first gen. millenium after the end of each charge.
im not sure if this is the correct formula but here goes:
charge time (in seconds) divided by 3600. then multiply by the amp rate
for example, charge time is 1500 seconds and rate is 6 amps.
1500/3600 = .4167
.4167 x 6000 = 2500mah
i think this is the same value shown in the first gen. millenium after the end of each charge.
We could simplify the above by putting it into and equation. Also, Nicads are fully charged up to 140% of their rated capacity. NiMHs are charge up to 150% of their rated capacity.
So for Nickel Cadmiums:
Charging Time (Hours) = 1.4*Rated Capacity(mAH)/Charging Current(Ampere)
Charging Current(Ampere) = 1.4* Rated Capacity / Charging Time
for Nickel Metal Hydrides:
Charging Time (Hours) = 1.5*Rated Capacity(mAH)/Charging Current(Ampere)
Charging Current(Ampere) = 1.5* Rated Capacity / Charging Time
This is according to a literature accompanying a Charger design I found in a local electronics magazine. In the absence of a peak detect charger, I usually follow the formula for Nicads, but for NiMH, only charge up to 100% of the rated capacity. No 40% over charge...
#78
sorry, i got used to that formula
#79
Tech Regular
mAh = milliampere * hour, which means stored energy.
#80
oops
Originally posted by JesseT
mAh = milliampere * hour, which means stored energy.
mAh = milliampere * hour, which means stored energy.
For Nickel Cadmiums:
Charging Time (Hours) = 1.4*Rated Capacity(mAH)/Charging Current(milliAmpere)
Charging Current(milliAmpere) = 1.4* Rated Capacity / Charging Time
for Nickel Metal Hydrides:
Charging Time (Hours) = 1.5*Rated Capacity(mAH)/Charging Current(milliAmpere)
Charging Current(milliAmpere) = 1.5* Rated Capacity / Charging Time
Thanks JesseT
#81
Shoot, everyone is making things complicated -
rule of thumb is - lower the mAh rating, the more punch, the less run time, the higher the rating, the less punch, the more run time.
Nobody can argue that 3000's have as much punch as a set of 1400's. . .
And it's a rule of thumb. . .
rule of thumb is - lower the mAh rating, the more punch, the less run time, the higher the rating, the less punch, the more run time.
Nobody can argue that 3000's have as much punch as a set of 1400's. . .
And it's a rule of thumb. . .