gbfan

My Feedback: (3)

Hey guys I got a few of these batteries and I
charge them with the old wall wart charger that comes with
the radio. I am wanting to leave them on their all
the time 24 /7 they take a long time to charge at 50 ma 5.75 volt
Anyone know why I cant do this .
David

radfordc

My Feedback: (14)

Should work.

http://batteryuniversity.com/learn/a..._metal_hydride

http://www.powerstream.com/NiMH.htm

You're charging at .02C

Steve Percifield

My Feedback: (14)

The wall wart charger needs to have a higher voltage than the battery you are charging..

jetmech05

I wouldn't do it....in my mind it's just not safe....
instead get a good charger and charge before you go to the field

DGrant

My Feedback: (4)

Yep.... Spend $30 or so at HobbyKing and get the correct charger. A decent battery charger is one of the best investments you can make in this hobby... as the batteries are the heartbeat of your plane... and a decent charger(again about $30 or so..) will charge your battery in one hour... and you will know its charged... as using a wall-wart style charger you will only be guessing at the amount of charge its taking... especially with a 2500mah batt, and a 50mah charger.. and you won't know when it peaks... whereas a peak charger detects a battery that is full...

So... I see no reason why you can't charge the way you're contemplating.... other then you're taking a very big risk with your plane.... but its your plane... Only you can make that call. I definitely would recommend a better charger though.

Rodney

You should have no problem charging with that old wall wart, it will just take a long time to recharge a fully discharged battery. In fact, charging at that low rate is much easier on your battery than the fast chargers are. Even if you get a new charger, when time permits, charge at 0.1C for longest battery life (most charge, recharge cycles for life of battery).

raptureboy

If your charger does not have enough amps it will never reach full charge. Chargers that come with the radio are designed around the 4 cell 900Mah batteries that come with most chargers. Get a real charger as suggested and don't leave any battery on 24/7 it can damage the battery. You can set a timer to charge a set # of hours per day. Check out these articles http://www.hangtimes.com/redsbatteryclinic.html

raptureboy

duplicate

tazzzz

I use the HOBBICO ACCU CYCLE ELITE. love this charger,,,I have 2 of them,,,,very reliable.

jaka

Hi!
When charging NiMH batteries never thrust a modern computer charger. The problem with those is that the NiMh battery is always false peaking which stops the charging prematurely
Instead use an old fashioned 100-300mAh wall charger, like that you have but a little bit stronger.

j.duncker

My Feedback: (2)

If your Walwart output is limited to 5.75 volts you can leave a 5 cell pack on forever because it will never get anywhere near a full charge.

A 5 cell NiMH pack needs a charging voltage somewhere between 7 and 7.5 volts to reach full charge.

So you need a suitable charger, one that can cope with the required voltage.

Rodney

Most of those wall wart chargers put out much more than 7 volts open circuit. When you put a load on it, the internal impedance drops that down. In all cases I've ever seen the wall wart will charge 6 cell Nixx just fine, just takes a longer time as the current drops off when charging the battery with more than 4 cells but does not stop and will provide a full charge given enough time.