Motorcycle 12v battery How to make one?

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jon218white

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Jul 18, 2019
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135
Hello
Would really like to make a 12v battery for my bike, it has a cranking value of 170a max.

I plan to use 1860s high current output, just unsure of how many s's to use, as not sure of voltage range my bike can work on, it charges led acid battery at 14.5v.

Or is it best to use lipo batterys? I known its hard to get 12v using lithium, but there are lithium batteries for bikes now just wondering how they do it?

Unsure how to change each cell use a dc to dc step down supply?
 
Last edited:

Wolf

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Sep 25, 2018
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For a 12V Pb replacement it would be best to go with Lifepo4. The Voltage similarities between a 4s *p Lifepo4 to Pb is perfect.
Each cell is 3.2V nominal X 4 is 12.8 Nominal. Also alternator/generator charging voltage is within the Lifepo4 acceptable parameters.
Wolf
 

jon218white

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Jul 18, 2019
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Thank you lipos on order
 

not2bme

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Oct 16, 2017
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I used 4 of the headway batteries to make my bike battery. It has screw terminals so linking four of them was pretty easy. No BMS but I don't ride that often so I just check it once in a while. No more dead batteries after the winter is over. Excellent.

 

Overmind

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Jan 16, 2019
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Agreed with LiFePo4s for 12V. For 24V it's fine to use Li-Ion but for 12 we're something in-between 3S and 4S. 3 would get OC'ed, 4 would get OD'ed.
 

jon218white

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Jul 18, 2019
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Thanks i ordered these was thinking of using the headway cells but import duty is so much,
Anyway im a but concerned about the charging volrage that the 4s will be sitting at when bike is on tickover its 14. 5v but thats measured on a lead acid battery, not sure what the voltage will be on lifepo4 battery.
Jst a bit concerned it will damage the cells as max they should be 12.8v
 

Korishan

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Jan 7, 2017
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LiFePO4 is basically a direct replacement for lead acid in increments of 4s
Charged is 3.6, which is 14.4V
Discharged is about 2.8, which would be 11.2V.
Even though they state that 2V is discharged, I wouldn't take them down that far. The 3.2V is "nominal" voltage, this is not that same as peak voltage.

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jon218white

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Jul 18, 2019
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135
i did ask for a data sheet to check upper voltage level.
Will get the soldering iron out now.

Thank you
 
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