# Battery percentage checker

going to run 8s3p cells so question is, the voltage indicators on eBay ( cheap ones ) rated between 3s to 15s only do 12v 24v 36v them 48v but my setup is 33,6v so how do I do? will it work or what?

The volt value will still be correct, only the percentage will be off by a small amount.

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so if I buy one I should put it at 36v?

Correct, 36v.

yeah do you know how many percent the difference will be? I assume silmillar to like 95% is 10%?

100%/x%=36/33.6 (100/x)*x=(36/33.6)x - we multiply both sides of the equation by x 100=1.0714285714286x - we divide both sides of the equation by (1.0714285714286) to get x 100/1.0714285714286=x 93.333333333333=x x=93.333333333333

now we have: 33.6 is 93.333333333333% of 36

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thanks alot

No worries.

Jesus. You couldâ€™ve just done 33.6/36 = 0.9333

E: BTDubs, thats not how those percentage meters work. Your battery capacity does not correlate linearly between 36V and 0V. There is a discharge curve between 42V and 30V for a 10S (36V) display. The percentage is mapped to voltage based on this curve. 36V is ~50% in this curve and 33.6V is ~10% so your display will almost always show 0% if you get that.

Look up LY6N or LY6W battery display. Those work for 8S too.

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Yeah Jesus donâ€™t worryâ€¦ cause he came back to life this weekend

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Completely forgot it was Easterâ€¦

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I think most of those meters do 12,24,36 and 48 with lead acid batteries but they also do 3s to 15s lithium batteries. This one does both: http://www.ebay.com/itm/12V-24v-36V-48V-Lead-acid-Lithium-Indicator-Battery-capacity-Tester-volt-meter/172018886570?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D40130%26meid%3Dd113753123854c1a95c8a63e1d5535d4%26pid%3D100005%26rk%3D5%26rkt%3D6%26mehot%3Dpp%26sd%3D331810603701

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Yeah so What do i do for A 8s setup?

He literally just pasted the instructions aboveâ€¦

yeah for 12,24,36 and 48V 8s is 33.6 literallyâ€¦