Lithium Battery Charge Time

[marty]

My Bionx 36V - 9.6 Ah Li-ion bicycle battery takes many hours to charge. Like all night.

My Makita 18V - 3 Ah Li-ion power tool batteries take about 30 minutes to charge.

Would 6 Makita batteries roughly equal one Bionx battery? Would you write 3S, 3P? S = Series, P = Parallel

Makita chargers have a fan that makes annoying noise. Only comes on when room temperature is hot.

Does any one make a fast charging electric bicycle battery? Takes me about 30 minutes to sit down and eat some food. Would be nice to be able to charge battery in that time.

 

[pwbset]

The Bionx use the US18650V cells right? 10s6p right? Same cell as the Makita. 4.2v max charge per cell 3.7v nominal. That Bionx charger must be sloooow amp-wise if it's taking that long. You could use any old dumb 37v lipo charger for the Bionx kit I bet... like the one from batteryspace.com below. I own this charger and use it on a 37v6ah konion pack and it charges in about 2.5hrs @ 3a.

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=4211

EDIT: Still @ 9.6ah (doubt you'll actually see 9.6ah.. more like 8.8-9ah under load I bet) you're looking at 9.6*1.5/3 = 4.8hrs to full charge. What's the Bionx LVC?

EDIT 2: Here's a 5a that will take charge time down to around 2.8hrs... kinda pricey @ $100 though.

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=4651

 

[Anonymous]

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[marty]

The Bionx use the US18650V cells right? 10s6p right? Same cell as the Makita. 4.2v max charge per cell 3.7v nominal. That Bionx charger must be sloooow amp-wise if it's taking that long. You could use any old dumb 37v lipo charger for the Bionx kit I bet... like the one from batteryspace.com below. I own this charger and use it on a 37v6ah konion pack and it charges in about 2.5hrs @ 3a.

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=4211

EDIT: Still @ 9.6ah (doubt you'll actually see 9.6ah.. more like 8.8-9ah under load I bet) you're looking at 9.6*1.5/3 = 4.8hrs to full charge. What's the Bionx LVC?

EDIT 2: Here's a 5a that will take charge time down to around 2.8hrs... kinda pricey @ $100 though.

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=4651

2.5 hours, 2.8 hours is a very long time. I WANT 30 minutes!
Take a look at this.
Makita Battery Dock

 

[pwbset]

I WANT 30 minutes!

:lol: Never run a charger in series if that's what you're thinking with the 18v Makita chargers. You could get a cheap high-amp power supply off ebay and modify it to work at 42v or whatever. I think I'm too stupid/drunk to see what you're getting at. N&V mentions BMS... good point, but konions typically don't need one except LVC/max discharge (fuse?) maybe. The Makitas and Boschs certainly don't have one... does the Bionx? If it does why not just bypass it?

 

[Anonymous]

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[pwbset]

Isn't LVC plus max discharge limit exactly what a BMS is?

That's kind of a good question if you think about it. To me the primary function of a BMS would be to balance the cells during charging since it's (relatively) easy to keep track of LVC and max discharge with things like a CA, but unless you're doing the single charger solution it's really hard to balance a pack without a BMS... in fact I don't think there would be a way to do that without a BMS... that I know of.

That's why I really want a konion pack so I don't have to worry (much) about balancing during charge. Frankly, and this is based on my complete ignorance of the industry in general (haha), I'm amazed that battery manufacturers create cells that would require balancing if the option was there, like konions, to not have to deal with it. Seems kind of Rube Goldbergian to me. K.I.S.S. :lol: