What BMS will I need with two VESCs?

ESK8 Electronics
1

Hey,

I would like to build a battery pack for my E-Board. It will probably be a 10s2p, not sure about it yet. I am going to have x2 Maytech VESCs with a current of 50A each. What kind of BMS will I need, in terms of amps? And do the dual motors that I am going to use will make a difference as well?

Thanks.

2

We don’t know what motors you are using Or what lithium cells you are gonna use for your battery

3

You probably right lol. I am going to use Samsung 18650 30Q, the motors are Maytech 6355 200kv.

IMG_3402.jpg739Ă—322 27.7 KB

4

200 KV is good for 10s and 30Q are said to be very good cells but I don’t think your gonna be happy with a 10s2p. You would do much better with 10s4p The 3510w max power is most likely a misprint Normally a 6355 190kv with 80a max will be rated around 2200-2400w I have not seen 3000w from anything smaller than a 6374 I would suggest a motor that can handle 80a anyway.

5

I’ll contact Maytech and ask for more details about it. Will update here.

So what do you think will be the BMS that I’ll need to be using? More specific, the amp rate of it?

Thanks.

6

This one: it has a built in anti-spark on/off switch and is rated for discharge 80a continuous and up to 240a peak Charge 20a I run dual vescs set at 80a motor and 60a battery each and have no problem at all with this bms.

http://bestechpower.com/37v10spcmbmspcbforli-ionli-polymerbatterypack/PCM-D223V1.html

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7

Perfect! Much appreciated.

Sorry for being noob, do I need to contact them in order to get price quote and ordering?

8

All their sales are through email They accept PayPal Somebody recently mentioned on another thread that they had an extra for sale.

9

Thanks for the reference, however I am not from the US so shipping from there might be more expensive then from the supplier itself.

10

Where you from

11

I live in Israel.

12

Bestech has a distributor in Germany

13

Cool, is there any way to contact them directly?

14

Email sales dept

15

you could also not use a bms. just put balance leads on your packs and you can balance charge with any $30 hobby charger. You don’t need balancing or management for discharging.

16

why not use a cheapo BMS and use it for charging only?

17

Those BMS includes e-switch with them so instead of buying an anti-spark switch for about 50$ I can buy a BMS + e-switch for 40$.

18

If my motor is rated as 65A for max current, will it be okay to use the BMS you suggested? In the BMS specs I can see “10S-80A working current”. Does it only related for the charging?

Another thing - I saw people here asked from the manufacture to ship their BMS with specific settings for cutoff start and cutoff end. I’m pretty noob when it comes to it so I’ll be more then thankful if you can help me decide what settings should I ask from the manufacture to set mine.

Thanks!

19

The bms can handle 80a continuous discharge, up to 240a peak discharge and 20a charge. I run dual drive. Each vesc is set to 80a motor max and 50a battery max. That’s 160a and 100a total and I have no problem with the vesc or the bms overheating. And I’ve got everything inside an almost air tight enclosure. NOTE: I’m running Ollin 4.12 Vescs with heatsinks.

Here are the settings I use:

HCX-D223V1 specs:Lipo.png599Ă—764 157 KB

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20

Thank you for your swift reply, much appreciated.

My setup will include x2 Maytech VESCs and dual [Maytech 6355 200kv motors] (https://www.aliexpress.com/item/Maytech-electric-bike-3000w-6355-200KV-mountainboard-motor-with-hall-sensor/32718907347.html?ws_ab_test=searchweb0_0,searchweb201602_5_10152_10065_10151_10068_10172_10084_10083_10080_10307_10082_10081_10110_10137_10111_10060_10112_10113_10155_10114_10154_10056_10055_10054_10312_10313_10059_10314_10315_100031_10099_10078_10079_10103_10073_10102_10052_10053_10142_10107_10050_10051,searchweb201603_5,ppcSwitch_5&btsid=79225337-6e20-440e-876e-476de2863cd2&algo_expid=da355bd6-424d-4b54-a5dd-08d76dd4d6f2-5&algo_pvid=da355bd6-424d-4b54-a5dd-08d76dd4d6f2&transAbTest=ae803_2) (max current of 65A). Will probably use 30Q Samsung batteries, 10S configuration.

Just to clarify - your settings are as follow: (1) Over charge detection voltage: 42.8V±0.025V. (2) Over charge release voltage: 4.08v±0.05V. (3) Over discharge detection voltage: 3.00V±0.05V. (4) Over discharge release voltage: 3.00V±0.1V (5) Over current detection voltage: 0.1V~0.2V

Considering all the parts I use for my setup, will you suggest me to apply your settings for my BMS?

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