Battery ??

[John D.]

Goob Morning Everyone,
Last year I purchased 8 ENERGIZER rechargeable batteries and a charger. I would recharged them and they would last many hours. This year I will charge them and use them for two or three hours, shut down my detector and a few days later I will check my 1350 before I go out and I have 1 bar on the battery check. Is this normal or am I doing something wrong on my charging procedure??
Thank You in advance for your help.
Your Friend,

 

[BigCatDaddy]

Nimh or NiCad??

 

[John D.]

Nimh

 

[Uncle Willy]

Since rechargeables are lower voltage they don't read as high on the battery indicator. After mine have been in a couple of hours they drop down to two bars on the indicator and remain there until the batteries reach the point of recharging. It's normal.

Bill

 

[NM5K]

Sounds like one or more of them are bad.
When this happens, take them all out and
read the voltage with a digital voltmeter.
If you see one that is quite a bit lower
than the others, it's probably about toast.
Rechargables don't usually keep a charge as
long as alkies, but you really shouldn't see
a big drop off after just a few days.
Slow charging is the best. The usual rating would
be at 10% capability for appx 15 hours. But this
will vary to type, condition, etc..
IE: Say the combined battery capability was 1000 mah..
You would charge at appx 100 ma for 15 hours.
You can tell when they are fully charged, as you
will reach a full float voltage which will stabilize
and not rise any farther.. Time to unhook..
The nimh batteries actually reach a float voltage
and slightly decrease a bit after a while. This
is why they make the two types of automatic chargers
for nicads vs nimh.. Most of the nimh chargers detect
the slight voltage drop as the indication to cut off.
Also, when rechargables start going bad, they usually
charge faster, and run down quicker. A good battery
should take a good while if you charge at 10%. IE: up to
15 hours or so.. The same type that is about shot might
get to float in 4 hours.. It's capacity is shot..
You can't get out, what you can't put in.
As an example of float voltage, a 13.8 volt car
battery will reach 14.4 volts when fully charged, and
stay there until you turn off the charger if not automatic.
If you read that voltage, you know it's fully charged.
Keeping the charger on at any decent rate will just overheat
and possibly damage the battery. When you turn it off, it
will slowly creep down to about 13.8v.
This can be used with any type of normal batteries..
You just adjust for the number of cells..
A single 1.2 volt cell should float right at about 1.4
volts when fully charged.
So say a 6 pack that gave 7.2v rated, would float at about
8.4 volts when fully charged. Four cells at 4.8 v, should
float at about 5.6 volts.
Myself...I use alkies.. I want my full 6 volts from my
four cells.. Or at least with fresh batteries anyway.
Anyway, thats a method you can use if you really want
to know for sure if you are fully charged or not..
They say the newer lithium batteries are not as picky
about charge schedules as the older versions.. But
I have lithium's in my newer cell fone, and so far they seem
to be basically junk to me. I think I did better with the older
nicads and nickle hydrides.. My lithiums are already flaking
out, and I charge em fairly normal too.
MK

 

[John-Edmonton]

Check to see if the GTP 1350 battery check is set on recharge-ables or not. Also, Nickel Metal hydrate batteries will discharge on their own, and a lot more if they have bin charged many times. Also, a lot of the quick chargers don't fully charge up the battery. The best chargers are the ones that take at least several hours to build up a charge.

Hope this helps......

 

[Uncle Willy]

Depends on the rechargeables. The ones I use last four times longer than an alkaline before needing a charge.

Bill