charging alkalines?

[PaperAirplane]

My Hitec Laser 4 came with a charger. The Tx has a NiCd but the reciever came with a holder for 4 AAA batteries. I used Duracells. It came with a charger for charging NiCds, and it is supposed to be able to charge the reciever battery. My question is can I charge the 4 AAA with that charger?

There was no NiCd reciever pack.


???


PA

[aramid]

No. You absolutely cannot charge alkaline batteries using any type of charger for any reason (notwithstanding special rechargeable alkalines, which I haven't seen in stores for years). Your charger is only acceptable for use with NiCD batteries - it has a receiver output because certain bundles of that radio system include a NiCD receiver pack, or so you can add your own NiCD.

If you'd like to go to a rechargeable receiver pack, make sure you get a NiCD pack if you intend to use your current charger - although NiMH packs are generally superior, they require a more advanced charger. Another option would be to switch to loose NiMH AAA (AA?) batteries like you might find at a drug store, along with whatever charger they come with or recommend.

Whatever you do, I suggest you stop using alkaline batteries for your receiver. They don't like that kind of load, and you should never take off unless you know your receiver pack is well-charged anyway, which you can't do with alkalines short of putting new ones in every day you fly.

You need to either use a BEC from your flight battery, or get a NiCD pack, or get an NiMH pack and a charger, or get some NiMH AAA/AA cells and a charger.

Alkalines are bad. Put them in your flashlight or TV remote control or something.

[PaperAirplane]

Actually, that is what I thought. I knew there were alkalines specific for recharging, just wanted to double check. Thanks.

[gramps2161]

Beg to differ there is a charger for alkaline batteries. The batteries can only be charged so many times with it they loose the ability to take a charge after awhile. It does work my wife bought it a while ago she uses it for her walkman. Yes I did say walkman. I wouldn't trust the charge for a RX though or the TX I tried it in a cheap esky TX was able to get 2 to 3 flights then the batterries whould loose their charge. This charger can only do alkaline batteries and they are regular alkaline batteries.

[PaperAirplane]

Originally Posted by gramps2161

Beg to differ there is a charger for alkaline batteries. The batteries can only be charged so many times with it they loose the ability to take a charge after awhile. It does work my wife bought it a while ago she uses it for her walkman. Yes I did say walkman. I wouldn't trust the charge for a RX though or the TX I tried it in a cheap esky TX was able to get 2 to 3 flights then the batterries whould loose their charge. This charger can only do alkaline batteries and they are regular alkaline batteries.

That sounds good for a walkman, but like you said, probably not very reliable.

By the way, how much power does the reciever usually take away from a battery pack that you are using to power a motor?

[gramps2161]

That depends on the RX how many servos you are using and what they are drawing for power to so now you have to figure what everything is using for volt's and amps. I just use my flight pack to power everything. Some of my 4 servo planes I use a ubec. If and when I get into the large rc planes then I will invest in a rx battery pack bigger planes can handle the extra wgt. of another battery. And no I wouldn't use the alkaline batteries in a rx. Like Aramid mentioned leave them to the flashlight and remote.

[aramid]

Originally Posted by PaperAirplane

By the way, how much power does the reciever usually take away from a battery pack that you are using to power a motor?

Nowhere near enough to worry about. If you're working your servos very hard, you might see a 5% decrease in total flight time. The absolute upper limit for most setups is the 3A rating on most small BECs. Even if you ignore how hard it would be to load the servos that much for a whole flight, a fairly standard 3s 2000 mAh battery has enough total energy to provide 3A at 6v for more than 90 minutes.

In practice, other factors like your mood and flying style, and even the weather, will have a much greater impact, as would the weight savings from flying without a receiver pack. If you spent a whole day flying the same model, some flights with a BEC and some with a receiver pack, and timed every flight with a stopwatch, I doubt you'd be able to come to a meaningful conclusion. The draw from the radio gear is just so much lower than the draw from the motor that it's basically irrelevant.

[PaperAirplane]

Thanks to both of you.

I will not worry about it then...

[flydiver]

I have a charger that was supposedly designed specifically to charge NiXX or ALKALINE loose batteries. It has a VERY SLOW charge rate. I have found that if you only use a small amount of the alkaline charge and re-charge it then it kinda works.
Discharge too far and it will appear to charge up but won't hold the charge. This is consistent with the instructions.

The BAD part the instructions DON'T TELL is the cells must take some harm because the tendency to become leaky and dump corrosive gunk into the electrics goes WAY up. I've stopped using it. The pittance saved is more than erroded in destroyed electrics.

I absolutely do not recommend charging alkaline cells if you value your electrics.

[PaperAirplane]

Once again, thanks.

[kyleservicetech]

Originally Posted by PaperAirplane

My Hitec Laser 4 came with a charger. The Tx has a NiCd but the reciever came with a holder for 4 AAA batteries. I used Duracells. It came with a charger for charging NiCds, and it is supposed to be able to charge the reciever battery. My question is can I charge the 4 AAA with that charger?


PA

I'm with the group on this, how many times have you had to shake your flashlight to get it to work with batteries? Not good for model airplanes. Also, just about any Nicad or Nih battery will far outperform an Alkaline battery, per my thread below:
http://www.wattflyer.com/forums/showthread.php?t=50934

[aramid]

Originally Posted by kyleservicetech

I'm with the group on this, how many times have you had to shake your flashlight to get it to work with batteries? Not good for model airplanes. Also, just about any Nicad or Nih battery will far outperform an Alkaline battery, per my thread below:
http://www.wattflyer.com/forums/showthread.php?t=50934

Needing to shake your flashlight is because of low-quality or corroded terminals - it's the mark of a cheap flashlight rather than of poor batteries.

However, your testing very clearly demonstrates why alkalines are a very bad idea for any high-drain use (which includes receiver packs). Your 500mA test is just about the limit for a normal name-brand alkaline, and even then you're only getting half of the cell's full capacity (they give you more total power if you treat them gently). A really high-end alkaline meant for high-drain uses like an Energizer E2 or Duracell Ultra can give you as much as 1 Amp before they start to really hurt (and once again only give you half capacity). By contrast, a thoroughly average NiMH battery can supply something like 4 Amps before it starts to give in.

Alkalines are still pretty safe to use in your transmitter, since that doesn't have the drain of servos. You could probably get a few months out of a set that way, but if you use rechargeables you can very easily make sure your radio is always fully charged and ready to go.

[PaperAirplane]

Sounds good. NiMhs also sometimes save money in the end.