Charging 2400mAH rx batteries.

[marktigere1]

Hi

I have a 1400maH RX battery pack in my Shuttle which I am about to replace with a 2400mAH battery pack.

Whilst discharging is handled by my trusty Futaba BR2000, what do people recommend for charging?

Is the standard charger okay (but takes a long time, 34 hours at a quick guess) or do I need to invest in a serious charger?

Money is an issue so I'm hoping I can stick with the standard charger for the time being before investing in a peak charger.

Cheers

Mark

[Janek]

I assume you're talking about the "wall" charger supplied with the radio gear ?, if it's like mine, it has a lead for the Rx and Tx, this is OK, although slow.

Check the label, it'll give you an output current for each lead. just divide the Rx number into 2400, that'll give you the approximate time to reach full charge. i.e If the label says 100mA, 2400/100 is 24 hours.

[Thomas]

Never used the wall charger, I'd put it in the bin, I use my Schulze for everything - glow stick, TX, RX, LiPo and kids toys

We had a bloke at the club with a Skidooo that he'd left charging overnight on a wall charger and he could not work out why it was conking out on him - was Ade who pointed out his battery was flat.

With a proper charger you can keep an eye on how much is going in too and do charge/discharge cycles, plus do a quick charge at the field.

[marktigere1]

Thanks for the replies chaps.

Janek, yes the wall charger is the one supplied with the FF7. I believe its a 70mA charge rate giving a charge time of 34 hours!!!!!

Thomas, I hope to get a proper peak charger in the near future which is the safest method of charging as you say.

Cheers

Mark

[Thomas]

there is one on BMFA if you are quick

[Ade_Law]

those wall socket chargers are not enough to charge the battery at any rate. Due to losses in the battery you will be lucky if it puts ANY charge in it!

the propeak prodigy is very cheap and will tell you exactly how much power its put in/taken out of the pack. only 55ukp too.

Ade

[marktigere1]

Thanks Thomas

Just checked and it's sold already

Thanks Ade, looks like I need to look at the whole electric charging situation.

Cheers

Mark

[jimbob]

The Simprop Intelli-control V3 charger is pretty much the same thing too and has never given me a problem.

Theres a new charger advertising in the mags now that runs off 12V and mains too. A nice feature.

[jamiem]

is it a set rule then that to find work out the charge time, i divide the pack capacity (2000MaH) by the charge current? i have a propeak charger with selectable charge rate (200mA up to 5A). what would be the safest maximum input as by my reconning it would charge the 2000mAh pack in about 25 minutes at full pelt. would this be safe?

Jamie

[Ade_Law]

its not recomended to charge at over 1c or you might damage. You also have to take into consideration as to what current the cables and connectors can take.

Also, if your charger doesnt detect the point at which the charging is complete its best not to charge at any faster than 0.1c

So for a 2000mah pack you could charge it at 2amps. However most batteries are fitted with the standard futaba/JR style connector will only take around 1.5-1.8amps without heating up. 0.1c charge for a 2000mah pack is 0.2amps.

charging at less than 0.1amps will probably not charge the battery at all due to the losses.

Ade

[jamiem]

the pack has a tamiya style connector aswell for charging. i think i need a charger with a peak detector. i will try it after next use. thanks again Ade

[Smoothound]

However most batteries are fitted with the standard futaba/JR style connector will only take around 1.5-1.8amps

So better beware if you are using good digital servos all round or you could have an auto waiting to happen

[Ade_Law]

they take time to heat up so its only a problem later in the charge rather than in flight.

as already mentioned the prodigy is great value.

Ade

[Kwickkwack]

Just Bought a Pro Peak Constellation Charger,
Does all my Li-pos, Nicads, Ni-MH, even lead acid, cost £80+, but having wrecked 2 li-pos at £27.00 each, thought this would be a better bet
Happy so far, and looking forward to improved battery reliability

Cheers
Bob

[Ade_Law]

thats what i use. great bit of kit.

Ade