DIY battery

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Yes I will feedback on how they go. The only problem I forsee if managing the spending
 
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As I look ad it, I can build the battery from 24ah without balancer and with shipping, for about the same as a 22ah with the other cells.
I must check the weight and dimensions, but as they are good, I am surtenty interested in them.
I will probably charge them with my hobby charger and just connect jst connectors to it and make them as 6s to charge.
 
Joined
Sep 14, 2013
Messages
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eire
As I look ad it, I can build the battery from 24ah without balancer and with shipping, for about the same as a 22ah with the other cells.
I must check the weight and dimensions, but as they are good, I am surtenty interested in them.
I will probably charge them with my hobby charger and just connect jst connectors to it and make them as 6s to charge.
They look like a serious supplier of car chargers and battery stuff, this is probably just a side line to take advantage of their Chinese contacts.
 
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They look like a serious supplier of car chargers and battery stuff, this is probably just a side line to take advantage of their Chinese contacts.
It looks good.
Also, you don't need to weld ad all to connect them.
I am going to see what sizes and weight I get and what fits best on my bike.
I have a limited space and want to kee it light, because I get 2 batteries on it.
 
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Going to make my own bus bars out of copper pipe 6S end to end using the screw together feature, also going to use a BMS. Charger is going to be a bit of a problem but will probably go commercial from China
 
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Going to make my own bus bars out of copper pipe 6S end to end using the screw together feature, also going to use a BMS. Charger is going to be a bit of a problem but will probably go commercial from China
Bms for it from China will not be that expensive.
It makes it easier to charge also.
 
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I just ordered my cells. I went for these cells.
https://www.nkon.nl/lg-inr21700-m50-4850mah-7-3a-clear.html?___SID=U

It is the same price as I would have payed for the Samsung cells, but instead of 22ah, I have now 29,1ah and that gives me a battery of 1047,6wh.
So a nice big battery. I will get a second one, but for now, this is good.
Most people use 2 10ah batteries and with my 17,5ah that I already have, I have a lot more.

Suze is 21 diameter and 70mm long, so they are a bit bigger, but the pack in total will not be that big.
I expect them Wednesday. I ordered them to late, to be shipped today, but I wasn't ad home to do so.
I could have went for a 24ah size, but I had safes tge money for the other cells and that made me decide to go for it. Better to big than yo small.
With a 350w motor, it is good to have a bit bigger.
 
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Going to see if mine will fit into a square PVC gutter downpipe - though the tolerances are very tight at 1mm spare.
 
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That's a good price for the power they give.
Yes they are normally used in cars.
Just crazy how much difference it is with as you buy a bike battery. Gazelle asked over 500 euro for 10ah.
As you go cheap here, you pay over 300 euro for a 10ah. I build a 29,1ah for under 300 euro with smart bms that I can setup on my pc and readout on my phone.

One disadvantage, charging takes a lot longer.
But I am ordering a 5a charger.
I have a 4a charger, but the one I get is better.
 
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I received my batteries today.


These cells make that I can make a compact battery.
I have now 2 versions in mind.
A 21x13,5x7cm or a 22x12x7cm pack.
It will be a bit bigger because of the head shrink, connecting plates and cables.

As I made it from 18650 batteries, than the pack would be about 21x15x6,5cm and only 22AH.
The 21700 with 4850mah make that the pack is more compact with more capacity.
 
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Decided to keep it simple.
Make 10 tows of 6 and just put them next yo each other. Will be a bit higher and a bit narrower pack. Then put all the cables on and head shrink around it. After that I mount the bms on top. This way I can reach the bms easier as is want yo connect it to the pc.
Printing now a 6 cell holder, so I can spot weld them.
 
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One advice, as you get a BMS, get a smart bms with bleutooth and one that you can connect to the pc and set it up.
You can set the max and minimum voltage, you can set it up for as you want yo store the battery, set the max charge and cut off different, so your battery gets a longer life.
You can watch on your phone how far the charge is or how much you still have and how much really went in and out.
2 temperature sensors so it stops as it is to heat or to cold.
 
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I am not happy. I connected the bms and everything looked good. I calibrated the cells and everything showed right.
I checked the power output and that made me unhappy. It gave 9v instead of the 36v that was going in the bms.
I contacted the company and they told me that the discharge was off. I tried to switch it on, but it doesn't want yo stay on.
Now I am mailing with them and hope that they can solve it.
Else I need to get a new one.
It is a great bms, because I can setup everything. I can ho on safe settings, change the cutoff with everything and even in temperature.
Balancing is great, because you can optimize your bms and monitoring your cells on your phone is great.
But sadly, I need to wait for a solution or a new bms.

Hope to hear soon from them.
The battery is big. I have still over 12ah in a battery that is just charged for storage. I didn't charge it yet, only tested it.
This gives me a great range, especially now I ride with low amps on my trike. Normally I reach 90km, but now with my new build, I have already over 60km and still over 60% in the battery.
 
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Got my cells today. Was surprised at how small they were. Going to build a pack which is 30cm long, 10cm tall and 7cm wide. Don't have a case or the BMS yet (haven't even dispatched from China yet) but will start linking them together and leave exposed tabs for the BMS.

Shoog
 
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Nice, by me it was the other way around. I got my bms but had to wait for the cells, till I decided to switch to othe cells.

I just use shrink wrap and black duck tape.
 
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Nice, by me it was the other way around. I got my bms but had to wait for the cells, till I decided to switch to othe cells.

I just use shrink wrap and black duck tape.
I am going to bind them with duck tape, separate layers with lino strips - but I want an outer case of metal or plastic.
Small size means that if I go for a second battery I can mount them on either side of the pannier carrier. without them taking to much space.

Shoog
 
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I mount also 2 on my bike and also one on each side.
Front also space for my 17,5ah battery.
So power enough as I have my second one.

I got the problem solved. It was a switch in an other menu what I had to change. Now I have power out.
Now I can finish my battery and start this week on the battery mount.
So happy that it works. Just crazy, 40% and still over 12ah in the battery.
 
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Made the cables for the battery. Solder them on tomorrow.
I have a 10s, battery meter that comes on it. It lihhrs leds as you press the button. Fast way to check the battery.
 
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