# How do you pick the right Amp Charger for your battery?

Just wondering if there is a formula to pick the fastest Amp Charger for a Battery Pack. I want the fastest charging Amp Charger but not to big if I am using a smaller Battery Pack.

dont go above 1c usually. 1c is weird but heres examples to explain. 9000mah = 9a = 1c 3400mah = 3.4a =1c 2874mah = 2.874a =1c

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@Richcan More amps = faster. General rule of thumb is, a 1Ah pack will charge in roughly one hour at one amp. Double the amps, twice as fast. Double the capacity, half as fast. (The charger slows down near full charge, so itâ€™ll actually be longer than that calculation would suggest, but not by a ton.)

More amps also stress the battery, reducing the lifetime of it. Most manufacturers will specify a maximum charge current - for 30Q cells, itâ€™s 4A per cell so a 10s2p pack would have a maximum charge of 8A.

Basically charge as slow as you can and still be happy with the speed. Fast charging is nice for you, but hard on the battery.

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So in your personal opinion, whatâ€™s the highest amperage youâ€™d charge a 5p 30q pack at?

I want to say 10 amp because itâ€™s a nice round 50% of max. My 4 amp charger wasnâ€™t ideal for all day riding in Colorado.

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60 amps at lowest state. If ur asking personal feelings. Maybe 40 to conserve the battery

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on a 12s4p i use an 8amp charger and takes about 75min from 20%â€¦ would never use anything less lolâ€¦ i would squeal in joy with a higher amp charger in the same form factorâ€¦ hmmâ€¦may have to play with the trim pots and see what i get =)

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I read people trim down the current with power supplies so they donâ€™t blow up. i too am on the quest for the smallest most powerful supply. I was thinking maybe could over- adjust some supply for high current and cool it with ice but read problems arenâ€™t just heat related.

Wish someone would design one that could take ice and whatever else and do the juice

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0.5c of a cell

So if your pack is 12AH

use a 6a charger

And plan ur ride for the next day or later.

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Well the spec of these cells tell you to charge at 1,5A. So to get the maximum battery life as specified by samsung, you would charge a 5p at 7,5Aâ€¦

The 4A value is the maximum the cells can handle, this is what I would use for the regenerative braking setting, with some marginâ€¦

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The variety of answers is suspicious.

Iâ€™ve heard 1c, 0.5c, 4A per parallel cells, and 1.5A per parallel cells.

Gonna go ahead and stick to an 8-10 amp charger and do more research into this.

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I have always heard the general rule of thumb is 1c, but they CAN charge at a higher current, it just degrades the cell life over time

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