Selecting the best value 18650 cells

[dmcp]

Hi. It's my first post here.

I'm shopping around for lithium cells to replace my old SLA, 48V12Ah. I think I'm going to settle with 75 panasonic ncr18650 PF, 5P15S. I included a pic to show my train of thought. I'm riding a stock PB710, about 10Km round trip to work and back, in Canadian winter weather soon again... maybe I should go 6P?? I came here to see what you much more experienced people would have to say.

ps. thanks for saying so much already, lurking this forum has been a huge help to me a few times now.

 

[999zip999]

So how much for a 15s 5p pack. Does it come with bms and how about a charger ?
Price with shipping.
Welcome to E.S. lot's of reading here on all 18650 cells. What's the amp rating of your controller ?
Reread I guess 375.00 for what a bms too ?
Check price of shipping.

 

[dmcp]

Just for the cells. The rest is on me.

Its a 17 amp controller. I plan to make the pack using 10 gauge so I may go bigger in the future.

I feel the need to clarify. The picture in the OP is a checkout bin full of all the different cells I could select for my pack. I made all the red writing.

 

[dmcp]

Let me rephrase my question.

What cell would you recommend me?

I want 15s for 63volts I drive a 48v pb710 with a 17A controller. Commute is 10km windy avg 15A draw. I use the bike all year round in -20c sometimes, but keep the battery indoors. I have old saggy SLAs, they won't last much longer.

 

[999zip999]

Those 10a rated cells are more than enough. Get them spot welded at the source in a series you can live with. 5s,6s and then you can solder across the spot welded tabs keeping the heat off the cells ( damp sponge ). I guess you have 75volt caps or higher in your controller ?

 

[dmcp]

Thanks. Yeah the cap says 63volt max, 15 in series at 4.2 v hot of the charger is 63volt exactly... match made in heaven

ps. those things are usually rated at 80% actually real life limits. wouldn't push it to full rating on anyone elses bike, but I'll risk my own controller. My SLA comes off a fresh charge at 58volts.

 

[markz]

Looking at your picture. If your red writing is correct. 25r's all the way!

Since you are Canadian, which province
Whats the website
Where are they selling from? Canada, USA, China
If China, min. $100 in s/h, then you need a charger, if from same company will add ~$20 s/h.

 

[999zip999]

You should have a pre charge resistor at lease you will easier on the caps. Rating ? Do know the limits. 63v battery 63 v caps ?

 

[dmcp]

Looking at your picture. If your red writing is correct. 25r's all the way!

25r's... that does seem to be a good choice, I may even bump it up to 6P 15Ah... With the 35A rating they should hold up best at ~3A/cell I want something that will last me a few years.

Since you are Canadian, which province

I'm in rural Niagara region, Ontario.

Whats the website
Where are they selling from? Canada, USA, China

from fasttech.com, free shipping, from Hong Kong, i have read some not so good reviews though so I may go with a North American supplier if I can find one. The prices vary by supplier, but most stay at a close ratio as for what cell costs more than others and how much.

If China, min. $100 in s/h, then you need a charger, if from same company will add ~$20 s/h.

A charger... I'm still not too sure about how I will be wiring this pack. My initial plan was simple 5P1S packs with two 10 AWG leads, marrette them in series for riding (with a fuse/set), then all in parallel for charging at 4.2V, but I'm sure if i read up on BMS's I'll figure out a better/faster system.

Do know the limits. 63v battery 63 v caps ?

If the cap blows at it's rated 63V then so be it. Now I feel like I'm tempting fate.

 

[999zip999]

A bms works on series cells. So 15s or a 14s is a more common bms. 1p 15s or for a bike 4p, more the better of quality cells. I like 15ah or bigger battery. Plus a proper charger cc~cv. No a sla charger.
I did say buy them spot welded in parallel set like 4or 6p ? Then you will be able to solder on the tabs as YOU SHOULDN'T SOLDER ON THE CELLS. You would need a big fat tip 60 or better 80 watt soldering iron. To solder in the middle of the tab ( no on top of cell. Do it quick with flux and a wet sponge to cool it down Fast.
Or just buy a ready made pack plug and play with charger and good cells to last. It must be the cells then ? What it's the cells ?