Quote from: saurabhhsrivastavaa on November 29, 2009, 02:55:10 PM
I beg to differ on this.. trickle charge is again a constant charge. the current is soo low that it is called trickle charge.

That is not what I see.  If you charger shows the current being applied, you can see that at least during the first 30% to 60% of the trickle charge phase, the current pulses between 0 and the max amps you have set for the battery.  For example, when I charge a 2200mah 6s lipo (used in Trex 500 helis), I always see that for a significant part of the trickle charge phase, the current pulses between 0 and about 2 amps.  And 2 amps is not that insignificant.  

Towards the end of the trickle charge phase, the pulse charge peaks do come down.

As long as you are happy no issues whatsoever..    However, I would not be surprised if you later change your thoughts.

Hi guys !!!

My charger shows a trickle charge of 0.01 A (10 ma) for a 12 v Pb Battery... and its continous... maybe tricke varies for different batteries. 

Appreciate all your time 

CHEERS 

well,folks i have broken my hand so i can't carry out with the discussion
when i'll be  fine i will tell u whats there in my mind
i thing i can tell u i will be tellling a method so that battery is not damaged
wait till then while u folks can carry out with the discussion

sorry to hear about your hand dear... all the very best and take care.. 

Well folks actually i m not able to understand the calculation because of my limited knowledge but as per my observation i have seen many things running on car batteries including loudspeakers[used while elections] and the most common car accessories including car chargers,car music players etc. and have no adverse affects on  the car battery

so why not a device to charge the batteries using it?
also i m not saying to take the batterries out of the car or even open the front cover[bonet or whatsoer its called]

QuoteIf you regularly charge Lipos out of car battery you would notice that the battery looses its performance very rapidly.

I spoke to a couple of people who, on the field, regularly charge their LiPos with their car batteries and none reported any problems. I think there is really no issue with 3S LiPos of the 2-3A range. 6S + high current could potentially cause trouble.

Saw some one charging two 6s 5000mah FlightMax packs for his Trex 600 *together* from his car battery today at the field (between the rains!).  He was using the 150W Turnigy charger from Hobbycity, and was excited about it !  The car was left running.

If he does this routinely, that should tell us something about the sanity of doing this.  Will check and report back in a few weeks.

He was sane enough to do it with the car running. That should protect him from draining the battery too much. Car batteries are not meant to be deep discharged. They have more thinner plates for high current bursts but discharging beyond 50% capacity is not recommended. Unlike deep cycle batteries meant for UPS. If you make a lot of short trips, your battery won't get time to charge. If you drive long distances, battery would be better charged. Atleast there is one good thing about having the flying field far away.

Hi,

A typical car alternator produces approx 1260 Watts of energy. (14V at 90 Amps)

6 Cell Lipo 5000 mah charging at 1C will consume only 126 Watts.. (6cells*4.2v*5amps) Rest is used for charging the car battery. Keeping the engine on while charging is a good idea. This should not create any problems.

Cheers !!!

Some time back somewhere I read that keeping the engine running while charging a battery is a big no no and that it would damage the charger 

Quote from: Rao on December 12, 2009, 03:53:46 PM
Some time back somewhere I read that keeping the engine running while charging a battery is a big no no and that it would damage the charger 

could anyone tell why i don't find any sound reason for it

http://www.ausrc.com/forum/showthread.php?t=11397

http://www.wattflyer.com/forums/showthread.php?t=31316

Conflicting opinions 

1) Do not keep the engine running, as there is possibility of surges that can damage various components.  It is better to keep the car running in idle for 5 minutes after the charging is done (as the alternator charges the battery pretty quick!).

2) Keeping it running is not a problem, but the problem is *starting* the car when the charger is working.  It causes spikes that the charges may not be designed to handle ?

So the thing is its better and safest to charge directly using the battery and not through any another thing in between-i.e.part of the car-i mean directly connecting charger to the battery
Am i right

Since I don't understand the question, guess someone else will respond 

i dont get it either ... 

sorry for confusing u all
i meant to say that to charge a battery we need to directly use the battery as the input to the charger/battery and not use the cigarette lighter plug or anything else or charge the battery when the engine is running
Am i right now?

Some more discussion on this topic here :

http://www.rcindia.org/batteries-and-chargers/charging-lipo-with-vehicle-battery/

anwar bhaiya i think all these topics must be merged tigether into one so it will be easier for the people to respond and to browse through these discussions
there are 2-4 discussions on the same topic