Battery Pack Charging - Changing Batteries
 

I have a battery pack from a Uniden scanner that won't hold a charge
any more. The pack has the charger circuit built in, and the
batteries are nicads in a pack of six AA size cells of 600 mAh
capacity. The charger circuit receives an input of 12v at 500 mAh
from a wall-knob. If I replaced the 600 mAh batteries with 1200 mAh
batteries what would be the effect on the charger? Would it just take
longer to charge, or?? If I am going to replace the batteries I would
like to increase the capacity at the same time.

The pack will still take a charge. Charging voltage at the batteries
is 8.5 volts. It just discharges fairly quickly. The radio is
probably 20 years-old, so it's a miracle the batteries lasted this
long.

Dick

Yes, no problem .. provided you stick with NiCad's. If you go to
NiMHydryde it may work, or it may not (or it may work for a while before
showing problems) Certainly Lithium Ion is out of the question.

I've replaced the cells in my two BP200 packs once or twice now and I'm
sure they are a higher capacity than original equipment .. but it's been
so long I don't remember exactly what they are.

Richard in Boston, MA, USA

Dick LeadWinger wrote:
: I have a battery pack from a Uniden scanner that won't hold a charge
: any more. The pack has the charger circuit built in, and the
: batteries are nicads in a pack of six AA size cells of 600 mAh
: capacity. The charger circuit receives an input of 12v at 500 mAh
: from a wall-knob. If I replaced the 600 mAh batteries with 1200 mAh
: batteries what would be the effect on the charger? Would it just take
: longer to charge, or?? If I am going to replace the batteries I would
: like to increase the capacity at the same time.

: The pack will still take a charge. Charging voltage at the batteries
: is 8.5 volts. It just discharges fairly quickly. The radio is
: probably 20 years-old, so it's a miracle the batteries lasted this
: long.

: Dick

Yes, no problem .. provided you stick with NiCad's. If you go to
NiMHydryde it may work, or it may not (or it may work for a while before
showing problems) Certainly Lithium Ion is out of the question.

I've replaced the cells in my two BP200 packs once or twice now and I'm
sure they are a higher capacity than original equipment .. but it's been
so long I don't remember exactly what they are.

Richard in Boston, MA, USA

Dick LeadWinger wrote:
: I have a battery pack from a Uniden scanner that won't hold a charge
: any more. The pack has the charger circuit built in, and the
: batteries are nicads in a pack of six AA size cells of 600 mAh
: capacity. The charger circuit receives an input of 12v at 500 mAh
: from a wall-knob. If I replaced the 600 mAh batteries with 1200 mAh
: batteries what would be the effect on the charger? Would it just take
: longer to charge, or?? If I am going to replace the batteries I would
: like to increase the capacity at the same time.

: The pack will still take a charge. Charging voltage at the batteries
: is 8.5 volts. It just discharges fairly quickly. The radio is
: probably 20 years-old, so it's a miracle the batteries lasted this
: long.

: Dick

On Sat, 03 Apr 2004 23:29:33 -0700, Dick LeadWinger wrote:

I have a battery pack from a Uniden scanner that won't hold a charge
any more. The pack has the charger circuit built in, and the
batteries are nicads in a pack of six AA size cells of 600 mAh
capacity. The charger circuit receives an input of 12v at 500 mAh
from a wall-knob. If I replaced the 600 mAh batteries with 1200 mAh
batteries what would be the effect on the charger? Would it just take
longer to charge, or?? If I am going to replace the batteries I would
like to increase the capacity at the same time.

The pack will still take a charge. Charging voltage at the batteries
is 8.5 volts. It just discharges fairly quickly. The radio is
probably 20 years-old, so it's a miracle the batteries lasted this
long.

Dick

Non-smart chargers for NiCad's are frequently a constant voltage with
current limiting or a more-or-less constant current.

Higher capacity is fine, it will take longer to charge. Keep an eye
out at hamfests, you can find NiMh AA's up to 2000 mAh or more. They
are good for cordless phones, too.

On Sat, 03 Apr 2004 23:29:33 -0700, Dick LeadWinger wrote:

I have a battery pack from a Uniden scanner that won't hold a charge
any more. The pack has the charger circuit built in, and the
batteries are nicads in a pack of six AA size cells of 600 mAh
capacity. The charger circuit receives an input of 12v at 500 mAh
from a wall-knob. If I replaced the 600 mAh batteries with 1200 mAh
batteries what would be the effect on the charger? Would it just take
longer to charge, or?? If I am going to replace the batteries I would
like to increase the capacity at the same time.

The pack will still take a charge. Charging voltage at the batteries
is 8.5 volts. It just discharges fairly quickly. The radio is
probably 20 years-old, so it's a miracle the batteries lasted this
long.

Dick

Non-smart chargers for NiCad's are frequently a constant voltage with
current limiting or a more-or-less constant current.

Higher capacity is fine, it will take longer to charge. Keep an eye
out at hamfests, you can find NiMh AA's up to 2000 mAh or more. They
are good for cordless phones, too.