|
Frequently
asked questions (Q & A) |
Q: Why the 1.2V
Ni-MH rechargeable batteries, especially low self
discharge battery, has much better performance
at high rate applications than the 1.5V alkaline
batteries?
A: NiMH batteries are spirally wound design compare
to a bobbin type design of a alkaline batteries.
The spirally wound design provides high electrode
surface area therefore the total current can be
much higher at a similar kinetics of the battery
electrochemical reaction. Due to the same reason,
Ni-MH batteries provide higher discharge voltage
than alkaline batteries. In addition, low self
discharge Ni-MH battery has longer storage period,
other than alkaline batteries. |
Q: Why should I choose NEXcell
rechargeable batteries over other types of
batteries?
A: NEXcell batteries
have longer cycle life, which means
you can save money comparing to rechargeable alkaline
of 50 recharges and non-rechargeable batteries.
Our batteries are also designed for power
intensive applications such as digital camera, the
batteries will maintain a high and consistent
voltage during its discharge cycle, unlike the other batteries
their voltage drop rapidly at high power demand
applications. NEXcell batteries
have lower impedance than the other brands in the
market. |
Q: What is the ¡°no memory
effect¡±?
A: The traditional Ni-Cd batteries world develop
memory effect problem if the batteries are discharged
at a fixed depth of discharge and then recharged
frequently before they have fully drained. ¡°No memory
effect¡± means that you can charge the batteries
anytime you like without worrying their performance
and battery life. |
Q: How long a rechargeable
battery will last?
A: The charge holding time of an unused rechargeable
battery at room temperature is about one to three
months depends on the storage temperature. The best
storage temperature range is 10 to 20 degree C. NEXcell
Ni-MH
batteries are rechargeable up to 500-1000 times,
lithium batteries are up to 1000~2000 cycles, depending on discharge and charge current and working
condition. |
Q: Why should I pay more
for the ¡°higher battery capacity¡±?
A: The capacity of rechargeable batteries is rated in ¡°mAh¡±
(mili-ampere hours). If the discharge current is
fixed, for example, 1000 mA, the higher capacity
means the battery will last longer so you would
pay for more in price. |
Q: What is conditioning?
A: The conditioning process is used first to drain
the charge from the batteries and then charging
them. Conditioning can allow batteries to perform
at their best standards and eliminate the memory
effect of Ni-Cd batteries. For Ni-MH batteries,
conditioning is recommended for every ten to twenty
charges. |
Q: Batteries should not leave
in the charger for a long period of trickle charging.
Why NEXcell charger can keep the battery
in the charger for long time?
A: We should not leave the rechargeable batteries
in the charger for a long period of time because
the batteries will be deteriorated by the trickle
charging current after long term charging. We recommend
to taking the batteries out of charger when the
charging is completed and keep them in a cool location.
However, NEXcell chargers do provide lower trickle
charging current for longer trickle charging time
compare to most of the chargers. Our Model 70 charger
provides an autostop function of trickle current
after batteries charged to full capacity and then
the batteries will be no current rest for seven
days and followed by a 200 mA charge for one hour.
The rest/one hour charge cycle will be repeated
as long as the battery is still maintained in the
charger. The battery will be kept full capacity
and without damaged by the trickle charge. This
unique design will allow user to store the batteries
in NEXcell charger with full capacity whenever we
need it. |
Q: Is it normal that the
batteries get warm when charging the rechargeable
batteries?
A: It is normal that the batteries will increase
temperature during charging Ni-MH or Ni-Cd rechargeable
batteries because the increase of internal resistance
and less energy conversion efficiency from electric
energy to chemical energy. We recommend you leave
the lid open during charging to reduce the heat
build up inside the charger. |
|
Q: How long will the rechargeable
batteries hold their charge?
A: Rechargeable batteries will self-discharging during
stand even left unused. The self-discharging rate
is depending on the storage temperature. You need
to recondition or charge the batteries several times
to restore the normal performance, if after long
storage. Generally lithium batteries have lower self
discharge rate than Ni-MH battery; Ni-MH battery
lower than Ni-CD battery.
NEXcell brand
batteries do provide a much longer shelf life
comparatively among all the battery brands. |
| ¡¡ |
| Battery
symbols and terminologies |
|
V |
Voltage represents the power level of the
battery. Just like the height of a reservoir.
For Ni-MH or Ni-Cd batteries, they are 1.2V
and the alkaline batteries are 1.5V. |
|
mAh |
The measurement of battery capacity, mili-ampere
hour. The number indicates how long the batteries
will last at certain power consumption. The
higher mAh batteries will last longer usage
time. |
|
mA |
The measurement of charging or discharging
current, mili-ampere. |
|
C |
The rate at which a battery is charging
or discharging. Discharging a battery at 0.2C
means to drain the battery capacity completely
in five hour. Charging a battery at 1C means
to charge the battery fully in one hour. 2C
charge means using the rate of twice a battery
capacity to charge the battery completely
in half hour. |
|
CmA |
During charging and discharging, CmA is
a value indicating current and expressed as
a multiple of nominal capacity. Substitute
¡°C¡± with the battery¡¯s nominal capacity when
calculating. |
|
| Other
technical terms: |
| Parallel charging of batteries |
| Sufficient care must be taken during
the design of the charger when charging batteries
connected in parallel. Consult NEXcell
when parallel charging is required |
| Reverse
charging |
| Charging with polarity reversed can
cause a reversal in battery polarity causing gas
pressure inside the battery to rise, which can activate
the safety vent, leading to alkaline electrolyte
leakage, rapid deterioration in cell performance,
battery swelling to battery bursts. Never attempt
reverse charging. |
| Overcharging |
| Avoid overcharging. Repeated overcharging
can lead to deterioration in battery performance
and may cause electrolyte leakage. |
| Rapid charging |
| To charge batteries rapidly, use
the specified charger or charging method recommended
by NEXcell and follow the correct procedures. |
| Trickle charging (continuous
charging at low current) |
| Carry out trickle charge by applying
the current of 0.02 to 0.05 CmA. The correct current
value is determined depending on the features and
purpose of the equipment. Long term trickle charge
is not recommended because it may deteriorate the
battery performance. |
