R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric Off-Road

Reply
 
Thread Tools Search this Thread
Old 03-14-2008, 06:03 AM   #1
Tech Addict
 
Join Date: Apr 2006
Posts: 522
Trader Rating: 40 (100%+)
Default Lipo charging/charger questions......

Can lipos be recharged after only like 1 qualifier or do they need to be ran down to cut off then charged? And what would the difference be in charging them with lets say a Trinity balanced A/C wall charger versus a LRP pulsar 3. Would they charge faster on the LRP?
jb7778 is offline   Reply With Quote
Old 03-14-2008, 06:24 AM   #2
Tech Regular
 
Alltapdout's Avatar
 
Join Date: Feb 2007
Location: Great White Buffalo
Posts: 412
Trader Rating: 2 (100%+)
Default

You can charge lipo's however you please. There is no real need to discharge them completely before the next charge.
Also, chargeing them with a ac/dc wall charger will do the job, but one thing to be aware of is the output. I think it would be safe to say that the pulsar can charge at a much higher rate, therefore it would take less time to charge your lipos.
Alltapdout is offline   Reply With Quote
Old 03-14-2008, 06:32 AM   #3
Tech Regular
 
beast95451's Avatar
 
Join Date: Mar 2007
Location: Kelseyville, CA
Posts: 273
Trader Rating: 13 (100%+)
Default

I don't know what the output of the wall charger is, but it probably is in milliamps & will take much longer. You want a charger that can charge at a 1C rate (ex: charge a 4800 lipo @ 4.8A. 3600 lipo @ 3.6A. 5000 lipo @ 5A) No need to run them to the cutoff. That's one of the benefits of going lipo, pull it off the track & plug it in. Top off & recharge as many times as you like.
beast95451 is offline   Reply With Quote
Old 03-14-2008, 08:07 AM   #4
Tech Addict
 
Join Date: Apr 2006
Posts: 522
Trader Rating: 40 (100%+)
Default

How does run time compare to NI MH? How much run time should you expect from say a 4500 lipo? Enough to get 2 or 3 qualifiers? I know motor, class and driving are going to vary but roughly?
jb7778 is offline   Reply With Quote
Old 03-14-2008, 08:12 AM   #5
Tech Regular
 
Alltapdout's Avatar
 
Join Date: Feb 2007
Location: Great White Buffalo
Posts: 412
Trader Rating: 2 (100%+)
Default

Two five minute quals should not be an issue.
Alltapdout is offline   Reply With Quote
Old 03-14-2008, 10:41 AM   #6
Tech Addict
 
Join Date: Apr 2006
Posts: 522
Trader Rating: 40 (100%+)
Default

Anyone used the Trinity Li-Pro batteries and charger? Good/Bad?
jb7778 is offline   Reply With Quote
Old 03-14-2008, 10:54 AM   #7
Tech Legend
 
Cain's Avatar
 
Join Date: May 2002
Location: West Fargo, North Dakota
Posts: 29,534
Trader Rating: 240 (100%+)
Default

The only issue I have been hearing about the trinity batteries is some issues with the built in cutoff sometimes kicking in when it shouldn't be. Not sure if this has been corrected.

I can recommend from my experience and what I have read here that Trakpower 4900mah lipos are really good and worth a look.

As for a charger, depends on what you want to spend and what info you believe you need.

Previously I had an MRC 989 charger and for the money it worked great combined with an LBA10+ balancer.

Now, I have a Hyperion 610i charger that has the built in balancer, and its one amazing charger. If you can afford it, I would definitely look into this charger for the money.

As for runtime, I would say you should be able to run 2 - 3 5 minute qualifiers without an issue with a 7.5 novak brushless motor or mamba 5700 motor.

The nice thing is you can repeak between qualifiers without a long wait unlink nimhs. So often, you just need 1 pack per vehicle.
__________________
Member - Red River Radio/Control Car Club
< Tekno EB48SL / SCT410.3 | Tekno EB410 x 2 | Yokomo YZ-2 DTM x 2 | LC Racing EMB-1 Buggies and Truggies >
Cain is offline   Reply With Quote
Old 03-14-2008, 11:19 AM   #8
Super Moderator
R/C Tech Elite Subscriber
 
Join Date: Oct 2007
Location: Rochester Hills Michigan
Posts: 7,232
Default

Do not discharge your lipos all the way down! Or even to the cutoff, break the habit. Lipos work far better, have higher voltage, and live longer if they stay in the upper 80% or higher range.

The only time to discharge lipos is to take them to 50% for storage. 3.8 volts per cell is usually recommended.
Dave H is offline   Reply With Quote
Old 03-14-2008, 11:41 AM   #9
Tech Champion
 
Jason Pelletier's Avatar
 
Join Date: Jul 2007
Location: New York
Posts: 8,820
Trader Rating: 33 (100%+)
Default

Quote:
Originally Posted by Alltapdout View Post
Two five minute quals should not be an issue.
Try more like 4 will not be a issue..... while running brushless of course. 5 min quali's
__________________
Island Raceway & Hobby
Jason Pelletier is offline   Reply With Quote
Old 03-14-2008, 11:43 AM   #10
Tech Champion
 
Jason Pelletier's Avatar
 
Join Date: Jul 2007
Location: New York
Posts: 8,820
Trader Rating: 33 (100%+)
Default

Quote:
Originally Posted by jb7778 View Post
Anyone used the Trinity Li-Pro batteries and charger? Good/Bad?
I hear there not bad but they don't have as much "punch" as the orions. Real world data from my racing buddy who uses both.
__________________
Island Raceway & Hobby
Jason Pelletier is offline   Reply With Quote
Old 03-14-2008, 12:17 PM   #11
Tech Legend
 
Cain's Avatar
 
Join Date: May 2002
Location: West Fargo, North Dakota
Posts: 29,534
Trader Rating: 240 (100%+)
Default

Quote:
Originally Posted by Dave H View Post
Do not discharge your lipos all the way down! Or even to the cutoff, break the habit. Lipos work far better, have higher voltage, and live longer if they stay in the upper 80% or higher range.

The only time to discharge lipos is to take them to 50% for storage. 3.8 volts per cell is usually recommended.
A nice feature of the 610i hyperion charger and I think some of there other ones as well is that you can set a capacity rating to charge to, and the charger can determine what capacity is already in the pack, and charge up to that point and stop. Not sure if it can do it to cell voltage though as I haved tried that yet.

I am highly impressed with this charger so far.
__________________
Member - Red River Radio/Control Car Club
< Tekno EB48SL / SCT410.3 | Tekno EB410 x 2 | Yokomo YZ-2 DTM x 2 | LC Racing EMB-1 Buggies and Truggies >
Cain is offline   Reply With Quote
Old 03-14-2008, 12:52 PM   #12
Super Moderator
R/C Tech Elite Subscriber
 
Join Date: Oct 2007
Location: Rochester Hills Michigan
Posts: 7,232
Default

Quote:
Originally Posted by Cain View Post
A nice feature of the 610i hyperion charger and I think some of there other ones as well is that you can set a capacity rating to charge to, and the charger can determine what capacity is already in the pack, and charge up to that point and stop. Not sure if it can do it to cell voltage though as I haved tried that yet.

I am highly impressed with this charger so far.
Excellent. Can it discharge to a certain level, or voltage? Which for us is more relevant, with brushless we need to discharge for storage, not charge. Even after 7 minute main and lots of screwing around after! The ICE will discharge to a voltage, but I'm thinking of upgrading to a balance charger, why I ask. BTW, the charge voltage on the ICE seems spot on, but not the discharge, I adjust the values to get what I want. I have one set at 3.5, one at 3.4, to get around the recommended 3.8 per cell storage voltage.
Dave H is offline   Reply With Quote
Old 03-14-2008, 01:50 PM   #13
Tech Addict
 
Join Date: Apr 2006
Posts: 522
Trader Rating: 40 (100%+)
Default

Forgive me I am very new to the lipo technology... What is the purpose of a balancer? You can't just charge the battery with a Pulsar 3 or the MRC989?? Is there a website with some more info on this topic?
jb7778 is offline   Reply With Quote
Old 03-14-2008, 02:02 PM   #14
Tech Champion
 
Jason Pelletier's Avatar
 
Join Date: Jul 2007
Location: New York
Posts: 8,820
Trader Rating: 33 (100%+)
Default

Quote:
Originally Posted by jb7778 View Post
Forgive me I am very new to the lipo technology... What is the purpose of a balancer? You can't just charge the battery with a Pulsar 3 or the MRC989?? Is there a website with some more info on this topic?
Yea you can i have 2 pulsar 3's and been using lipo's for 3 months. No balancer, although i tried my friends and one of my lipos was slightly out of balance. I notice no diff.
__________________
Island Raceway & Hobby
Jason Pelletier is offline   Reply With Quote
Old 03-14-2008, 02:21 PM   #15
Tech Legend
 
Cain's Avatar
 
Join Date: May 2002
Location: West Fargo, North Dakota
Posts: 29,534
Trader Rating: 240 (100%+)
Default

The point of balancing as I understand it is so that each cell in the pack is up to the same amount. If for some reason a cell is out of balance with the others, and you charge up the pack you could possibly either have an overcharge issue on the cell(s) that are higher in voltage, or, when using the pack assuming it stopped early on the charge, when you use the pack you could over discharge the cells that were at a lower voltage. I know there are companies that claim you don't need to balance there packs, but, I have heard of there packs in some hands being out of balance. I would rather error on the side of balancing a pack than risking one of those two scenarios listed above.

As for if the Hyperion charger can discharge to that voltage level I don't know. For my use, I run the packs out as I usually do a 20 minute main. You can however view the manual for the hyperion 610i to confirm. you cna get a quick link to it on www.rclipos.com site.
__________________
Member - Red River Radio/Control Car Club
< Tekno EB48SL / SCT410.3 | Tekno EB410 x 2 | Yokomo YZ-2 DTM x 2 | LC Racing EMB-1 Buggies and Truggies >
Cain is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Lipo Battery/Charger Questions jaminit Rookie Zone 8 09-09-2008 01:23 AM
Charging Amperage questions Allumina Radio and Electronics 5 08-02-2008 02:07 PM
Lipo Charging Questions nickjames Radio and Electronics 3 02-03-2008 07:30 PM
Lipo Charger questions rregl0612 Electric Off-Road 9 06-11-2007 11:20 PM
NEW LiPo Prototype Battery Charger Questions. ICT-POWER.COM Electric On-Road 18 08-25-2005 02:46 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 03:10 PM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net