My experience bulk charging lipo with BMS 400w charger

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atom1025   100 W

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My experience bulk charging lipo with BMS 400w charger

Post by atom1025 » Feb 21 2012 9:12pm

So I recently invested into bulk charging. I purchased the necessary cell protection from Methods and purchased two 400w chargers from BMS. One charger at work one at home.

I chose 4.10v per cell so 61.5v output at ~3amps. I only use 5amps to and fro so charging takes about two hours.

Been running this for a week now and love the plug and play charging.

So my concern. The resting voltage after charge reads 61.05v (4.07per cell)on the 101wattmeter. The resting voltage after commute is around 54-55v roughly 3.6 per cell.

So it appears I am only using the lower spectrum of my pack. Obviously power is down a hair on the way home. So my question to ya all is.... Do you think using the lower end causes more abuse to the pack then say using the upper?

So I am kinda thinking bout getting a new charger with 62v output. 4.13 per cell. Put me more into the upper mid range.... might try and modify these chargers, myself since they are paperweights if replaced...
Bashed Synergy Cycle runs
1800w peak, 31mph tops.

2004 Cannondale Jekyll with a MAC 10
15s 8ah lipo (2100w peak) 31mph tops.

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neptronix   100 GW

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Re: My experience bulk charging lipo with BMS 400w charger

Post by neptronix » Feb 21 2012 9:17pm

4.15v would provide you a decent amount of additional power, remember that these are normally charged to 4.2v/cell. So 4.15v/cell is still conservative.

3.6v is about where they are ready to start diving for 0v.. i usually stop at 3.45v/cell, anything lower than that, and the internal resistance rises to the point where the cells can actually disbalance themselves & start heating up.

( we're talking about RC Lipo ( lico ), i take it )

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wesnewell   100 GW

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Re: My experience bulk charging lipo with BMS 400w charger

Post by wesnewell » Feb 22 2012 2:47am

I'm pretty sure you can adjust the voltage on those chargers so there's no need to order another one. Just adjust the voltage up to 62V.
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miuan   10 kW

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Re: My experience bulk charging lipo with BMS 400w charger

Post by miuan » Feb 22 2012 3:18am

Theres a lone blue pot inside, at the corner of the board, that adjusts voltage. Take a thin screwdriver, turn it to get the desired voltage, as easy as that.

atom1025   100 W

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Re: My experience bulk charging lipo with BMS 400w charger

Post by atom1025 » Feb 23 2012 9:46pm

miuan wrote:Theres a lone blue pot inside, at the corner of the board, that adjusts voltage. Take a thin screwdriver, turn it to get the desired voltage, as easy as that.
Hells yeah! Easy peazy!

I adjusted up to 62v. The charger cutoff when pack reached 61.5v. So I adjusted it up to 62.5v and I hope it cuts off at 62v. I'm staring at it now monitoring temps and volts.
Bashed Synergy Cycle runs
1800w peak, 31mph tops.

2004 Cannondale Jekyll with a MAC 10
15s 8ah lipo (2100w peak) 31mph tops.

atom1025   100 W

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Posts: 173
Joined: Jun 01 2011 8:25pm
Location: Sacramento California

Re: My experience bulk charging lipo with BMS 400w charger

Post by atom1025 » Feb 23 2012 10:11pm

The charger cutoff @ 62.1v( measured at the pack leads) with the output voltage set at 62.5v.

It is indeed the blue stand alone pot in the corner by the fuse. Turn it counter clockwise to turn voltage up.
Bashed Synergy Cycle runs
1800w peak, 31mph tops.

2004 Cannondale Jekyll with a MAC 10
15s 8ah lipo (2100w peak) 31mph tops.

Scottyf   100 W

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Re: My experience bulk charging lipo with BMS 400w charger

Post by Scottyf » Mar 01 2012 4:05am

Just wondering if the smaller 240w bulk chargers also have a pot in them if anyone else know's?
I have a feeling their not but would be interested to know.

Might have to buy another bulk charger for my needs as there quite a bit simpler for charging 9 lipo bricks...

Just wondering as the 240w charger has the same case as the 400w. That obviously means its not garanteed to be the same. But it would be nice to know.
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docnjoj   100 GW

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Re: My experience bulk charging lipo with BMS 400w charger

Post by docnjoj » Mar 01 2012 3:57pm

Even my old Ping 2 amp charger has a voltage adjust pot. I had to cut it open to find it, but it works fine to adjust the voltage from 61 volts for a 48 volt pack to 45 volts for a 36 volt pack. Both have BMS that need the higher voltage to balance in these Signal lab BMS's.
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