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Old 03-05-2017, 03:03 PM   #1
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Default Lipo connector too small for rated discharge

Looking at couple batteries for high speed runs but concerned about connectors.

Looking at 2 batteries that come with removable cables...

Gens Ace 5300mah 65C, based on this it is capable of delivering 340+Amps yet it has 4mm bullets on 10awg

Turnigy Nano 6000mah 65C, capable of delivering 390A and also comes w 4mm bullets on 10awg

I thought 4mm are good for about 60-80A, what's the logic here? I know I can put 8mm bullets from battery to ESC, but the wires that plug direclty into the battery hardcase are still 4mm. Should batteries w removable cable be avoided since most come w 4mm? I've seen few that come with 5mm bullets that plug into hardcase but still, those are only for about 120A. Planning to draw 140-170A on 6S.

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Old 03-05-2017, 08:44 PM   #2
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Originally Posted by toothless23 View Post
Looking at couple batteries for high speed runs but concerned about connectors.

Looking at 2 batteries that come with removable cables...

Gens Ace 5300mah 65C, based on this it is capable of delivering 340+Amps yet it has 4mm bullets on 10awg

Turnigy Nano 6000mah 65C, capable of delivering 390A and also comes w 4mm bullets on 10awg

I thought 4mm are good for about 60-80A, what's the logic here? I know I can put 8mm bullets from battery to ESC, but the wires that plug direclty into the battery hardcase are still 4mm. Should batteries w removable cable be avoided since most come w 4mm? I've seen few that come with 5mm bullets that plug into hardcase but still, those are only for about 120A. Planning to draw 140-170A on 6S.

The logic is burst current. No little connector will hold that max current indefinitely and live, but it wont have to as it will hold for the fraction of a second your car will be under full load. Also, heat isn't a problem in the wires due to them seeing a lot of airflow. Most wire gauges are rated for amperage based on how much it will take if its in a wall with no airflow, but in an RC car it will get cooled quickly.
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Old 03-05-2017, 09:54 PM   #3
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the 6 cell helis use an ec5 connector like:
Female EC5 Connectors (4 Sets)

are you thinking of ganging together 3 batteries in series? (3x's 2cell packs) that would pull more current. it might be better to use one high rate 6cell pack, glacier are a good choice, clearly you aren't concerned about roar approval.
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Old 03-06-2017, 12:08 AM   #4
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There are plenty of batteries that have a rating of 120C burst, 60C continuous, and these go as high as 7500mah. Although with a 5mm connector. A clerk once gave me a very sound advice - don't always look for logic, because sometimes it just ain't there. This being one of those cases. The C rating is an imaginary value that cannot be measured, it's actually not even defined in any meaningful way. Like is it the value where the battery gets damaged/puffed, or when it blows up? Or will it not provide the current beyond the limit, regardless of the resistance applied eg when short circuited? Or is it when the weakest part melts away? So take those values with a very sceptical eye, and generally just use them to compare different batteries of one brand.
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Old 03-06-2017, 04:02 AM   #5
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You've just spotted the issue with all of the current rating BS that the cell people quote!!
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