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Old 02-03-2009, 05:52 PM   #1
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Default how to charge 6Kmah on 5K mah charger

I recently bought a triton eq and like it a lot.. But I'm wondering how does one charge these bigger mah battery packs, cause it's max is 5a=5000mah.

Say I wanted to charge a 2s 6500 lipo battery. How would I do that..

just set one charge to 5000 and another to 1500 or what?
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Old 02-03-2009, 05:58 PM   #2
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NO!!

overcharging lipos will cause bad things to happen, as well as undercharging them...

You will not beable to charge that battery with that charger... If you do it can very possibly cause problems!!
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Old 02-03-2009, 05:59 PM   #3
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Just set it to the 5000mah.. the charger uses that information to set the charge amp rate. It will just take longer to charge at less than the 1c rate. The cc/cv program will detect the pack voltage and adjust down toward the last bit as the volts near the max. Do not charge it twice.. no need.

If you have any doubts.. call or email your charger manufacturer.


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Old 02-03-2009, 06:01 PM   #4
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you can charge a lipo battery that is 6,000 on a charger with 5 amps set at 5,000,it just takes longer
lol we were typing at the same time
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Old 02-03-2009, 06:09 PM   #5
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that is why I asked cause I already asked the company that makes the chargers.. Here's what he said..

hank you for your email,

If you have a 8500mAh battery then yes you can charge to 5000mAh on one charge and an finish off the battery with the second charge of approximately 3500mAh. The maximum charge capacity for some of other chargers such as Great Planes ElectriFly Triton2 EQ AC/DC charger (GPMM3156) is 9900mAh.

Should you have any further questions or concerns, please do not hesitate to contact us at this email address. (Please be sure to copy all previous emails into any future questions.) You can also reach our product support technical team at 217-398-8970, or via fax at 217-398-7721.

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Old 02-03-2009, 06:12 PM   #6
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Quote:
Originally Posted by RyyRyy View Post
NO!!

overcharging lipos will cause bad things to happen, as well as undercharging them...

You will not beable to charge that battery with that charger... If you do it can very possibly cause problems!!
This is why the internets is so valuable......


Yes. You can charge it at 5AMP, it will just take much longer. Look into buying a higher output charger like a 10AMP Hyperion or something along those lines.
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Old 02-03-2009, 06:21 PM   #7
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ya, but they are not ac/dc compatible... I 90% of the time need it to plug into a wall though....
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Old 02-03-2009, 06:26 PM   #8
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Originally Posted by RyyRyy View Post
NO!!

overcharging lipos will cause bad things to happen, as well as undercharging them...

You will not beable to charge that battery with that charger... If you do it can very possibly cause problems!!
WRONG



As said, you can charge just fine at 5 amp it will take longer. Now, a lot of chargers have a timed cut-off when charging lipo batteries so if the charge gives you a time out code before it says it's fully charged you just have to start the charging process again to finish charging the battery.
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Old 02-03-2009, 06:54 PM   #9
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WRONG



As said, you can charge just fine at 5 amp it will take longer. Now, a lot of chargers have a timed cut-off when charging lipo batteries so if the charge gives you a time out code before it says it's fully charged you just have to start the charging process again to finish charging the battery.
^^^ what he said!
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Old 02-03-2009, 08:08 PM   #10
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WRONG



As said, you can charge just fine at 5 amp it will take longer. Now, a lot of chargers have a timed cut-off when charging lipo batteries so if the charge gives you a time out code before it says it's fully charged you just have to start the charging process again to finish charging the battery.
Well you may be right in this case, but there are some batteries out on the market that specifically instruct and warn not to undercharge...
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Old 02-03-2009, 09:42 PM   #11
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Charging at 5a instead of 6a is not undercharging at all... They usually just don't want you to "trickle" charge it in fear you might overcharge it...

The only disadvantage to charging at 5a instead of 6a is it will take SLIGHTLY longer to charge.

I say SLIGHTLY because the portion of the charge where it can go full speed (The CC part of the charge) is not that long usually anyway, it has to slow down as soon as the voltage hits 8.40... (The CV part of the charge).

My guess is if it would take 1 hour to charge at 6a it would take 1 hour and 15 minutes to charge at 5a at most. Not worth shelling out another $100+ for a new charger. Your current charger will work just fine, just tell the charger its a 5000 and it will do the rest...
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Old 02-03-2009, 10:55 PM   #12
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i had a 8000mah 4s pack and it seemed like forever before it finished charging
i have the triton eq

granted down the road the pack did eventually catch fire but only while at the track , no problems while testing at home and running in the street.
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Old 02-03-2009, 11:17 PM   #13
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i had a 8000mah 4s pack and it seemed like forever before it finished charging
i have the triton eq

granted down the road the pack did eventually catch fire but only while at the track , no problems while testing at home and running in the street.

Yes, that battery would take forever to charge with the triton eq charger. According to the charger specs it has a max 50 watt output when plugged into a wall. The formula to figure watts is volts x amps. Since we know the watts and the volts we can figure the amps. If you divide 50 (watts) with 14.8 (4s voltage) you get an amperage rate of 3.3783783783783783783783783783784

Basically your charger would only produce a 3.3 amp hour charge rate or 3378 milliamps per hour. If you ran your 8000mah batter to a 6 volt cut off then it would take about 2 hours and 20 minutes to charge it back up fully.
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Old 02-03-2009, 11:45 PM   #14
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Yes, that battery would take forever to charge with the triton eq charger. According to the charger specs it has a max 50 watt output when plugged into a wall. The formula to figure watts is volts x amps. Since we know the watts and the volts we can figure the amps. If you divide 50 (watts) with 14.8 (4s voltage) you get an amperage rate of 3.3783783783783783783783783783784

Basically your charger would only produce a 3.3 amp hour charge rate or 3378 milliamps per hour. If you ran your 8000mah batter to a 6 volt cut off then it would take about 2 hours and 20 minutes to charge it back up fully.
Actually it would take longer, it will only charge at 3.3a during the CC part of charging. Remember Li-po must be charged using a CC/CV method...
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Old 02-04-2009, 06:22 AM   #15
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Charging at 5a instead of 6a is not undercharging at all... They usually just don't want you to "trickle" charge it in fear you might overcharge it...

The only disadvantage to charging at 5a instead of 6a is it will take SLIGHTLY longer to charge.

I say SLIGHTLY because the portion of the charge where it can go full speed (The CC part of the charge) is not that long usually anyway, it has to slow down as soon as the voltage hits 8.40... (The CV part of the charge).

My guess is if it would take 1 hour to charge at 6a it would take 1 hour and 15 minutes to charge at 5a at most. Not worth shelling out another $100+ for a new charger. Your current charger will work just fine, just tell the charger its a 5000 and it will do the rest...

Trickle is way different... any current up to date Lipo specific charger does not have trickle on it...

Do what you please but I am confident in saying that it is not the healthiest thing you can do for your pack... Many people do not realize the danger that these batteries can bring and end up treating them like toys...

I've been using lipos even before they were brought to R/C cars... so believe me when I say i Know a bit about them...

Don't believe me? then take the yellow instruction sheet of any Thunder Power pack and skim through it, you'll see something there that says the same thing I wrote in my first post...
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