How do you know how long you need to charge a battery for?
assuming you know the how many amps you are putting in.
is there a way of working out how long you need to charge for.
if this has already been asked please point me to were.
thanks

There is no real way to find out how long to charge your battery's for . because there could still be power left in it.
Your charger has a peak detection and it will turn it self off when your done.

What kind of charger are you using ?

at the moment just a cheap timed one.

Those aren't very good and don't work properly. Save up your money and get a good peak detection charger.

http://cgi.ebay.com/Hitec-CG340-DELT...QQcmdZViewItem

is this any good?

No
this one is
http://cgi.ebay.com/Great-Planes-Ele...QQcmdZViewItem

If it were me I would spend just a little more and get this one. The Jr. has an auto shut off and will loose the information that was recorded. Here is Jr's daddy.

http://cgi.ebay.com/Triton-2-DC-Peak...QQcmdZViewItem

I usually speak about "charger" rather than "battery" because of what has been posted above. It is real simple.
Amps = amperes= amps per hour

A rate of 3 amps = 3 ah or 3000 mah. If you know your battery capacity and have used it up then you can easily estimate your charge time at 1 hour.


A peak charger is recommended for people like me who do not want to do the math or have a hard time keeping track of usage or who just want to know when it's full, it is also a safer way to go in case an error is made in figuring.

you could check its amps.. or maby the mah in the battery.
you would need a guage or light bulbs or somekind of thing,
to tell you.
most chargers have peak detection.
some older chargers don't.
some newer chargers with peak detection arn't
very accurate.
that is when it is always good to have a meter.
you should buy the temp guage thats in
the "usful tool" thread..
its a tempature guage that makes sure you don't overheat your batteries.

check the amps of what ? the battery ? it doesn't tell you it's done charging.
Light build is very inaccurate way . they are only meant for discharging quickly to put it on the charger.
and most all peak detection on charger are VERY accurate due to thew fact of the ristance is getting more and more.
the Super brain's how ever false peak A LOT . that is a charger that isn't very good.

yeah, wasn't soo sure on that.
i was saying if you could test how many mah the battery is putting out..
conpared to what they claim on the cell, you would know.
that it has reached top peak.
i have the duratrax digital pirahana accualy, there great chargers.
they charge 1-8 cells,
.1-5. amps,
they have many digital readouts..
for 49.99 you really can't beat the quality.

Only problem is you are limited to 8 cells
actually you aren't really
what is the max MAH that charger can go to ?

doesn't say...
just says amps..
i just charge my two 6 cell batteries on it for my sv27.
it works fine for what i need it to do.

-you have reply to pm

yeah . you can charge the battery's in parallel.
so you can feasibly do about 32 cells . it all depends on you MAX MAH it can charge

the problem, is that the charger gets very hot. i usualy have to let it cool before i can put the other battery on.

i have charged my friends ib4200's on it without a problem.

edit: Tailor operation to your specific battery types with these programmable features:
Feature Programmable Range
Battery Type NiCd, NiMH - 1-8 cells
Charge Current 0.1-5.0A
Battery Capacity 50-5000mAh
Peak Sensitivity 3-20mV
Trickle Current 0, 100, 200mA
Sounds 5


so 50-5000ma there ya go

The only batts that should be charged in parallel are ones that do not "peak" like a lipo where the voltage keeps climbing and coincidentally can also be measured for capacity.

There's not an accurate way to measure a nickel battery for remaining capacity unless it is very near the "full" mark or "empty" mark. A decent way is to time the run or just estimate it on known values.

Guver is absolutely right, this is very bad information. If the packs are in different states of discharge - which most would be - charging them in parallel is a great way to over-charge some of them, causing burst cells and ruined packs! Don't do it.


.

unless you have a 32 cell boat and you buy all the battery's at the same time with the same cycles threw them.
I have done it for abour 40 charges on 3200MAh cells with out a problem. Mind you they were always done the same

Chargeing multiple cells in series is also a bad idea if they are not all requiring the same amount of charge. I have heard of some people chargeing some parallel nickel packs, but I do have one question.

What happens to the first pack done (when the voltage starts to drop) As the voltage drops, it should start taking on more and more charge as the other packs with the higher voltage?

i only have to charge up to 6 cells, as i have a small boat, and a 2000mah battery and 1700mah battery.
i guess it would be handy to go up to 7 or 8 cells. Aslo i live in the uk so if it is AC powered it needs to be able to do 230v. Also need to be able to get it here.
importing is probably a good idea, as stuff over here is very very expensive.
thanks

If you know the rate of your timer charge then it is easily figured for your two batts. Divide total capacity delivered by the rate for the time .

There are plenty of 230V to 120V converters.