Battery Clearing House SV-BA10 13s 20Ah Battery

BenjaminF · May 6, 2020, 4:30am

You could also go with my strategy of popping the stock BMS like a porcupine pops his birthday balloons, and wire a charge only BMS.

RyEnd · May 6, 2020, 1:15pm

Jup.

Fosterqc · May 10, 2020, 9:19am

Did you already order one? They are out of stock.

Solar charger controllers are your friend, and so are we!

Fosterqc · May 10, 2020, 9:27am

Ok

I’m more of a hydroelectric guy myself.

Still need to make this giant battery usable…

Mr.Electronicist · May 10, 2020, 4:05pm

@Scepterr you were correct on the pins to enable charge/discharge. But there must be a overly sensitive short circuit sensing circuit, because if a single VESC is connected when you turn it on, it immediately turns back off. But if you turn it on and then connect it to the vesc it works fine.

Was able to remove the XLR port, and wire a switch and charge plug to the hole, and Bypassed the BMS for the output leads. Then tossed it on my brothers ebike and it’s been working great. He was able to get a nice 40 mile range out of the pack.

Scepterr · May 10, 2020, 4:05pm

great to hear

Fosterqc · June 4, 2020, 12:01am

Did you add in the dicharge port and BMS?

I’m thinking about getting a Buck Converter so I can use this pack to charge 12 and 6S packs.

https://www.amazon.com/Converter-DROK-Regulator-Constant-Adjustable/dp/B01MSJQAKY

PrivacyDoctor · June 4, 2020, 12:46am

Get an HP dps-1200 server PSU and a boost Converter:

Details on the psu:

github.com

slundell/dps_charger/blob/master/README.md

# Afterthought
This project turned out to be bigger than I first anticipated. My main aim is still to make a competent battery charger, but a few steps needs to be taken along the way. First, reverse engineering and documentation. Currently most of the documentation is in this readme. I have started a KiCAD project to document the circuits of the CPU board in doc/kicad/. High resolution images of the CPU board is available here and in doc/images/. This can be used for reverse engineering the circuitry. 

The i2c reverse engineering is done with an ESP8266 using various methods and experiments. Code is in `src/dps_re.cpp`. The charger project is split up in two approaches. An analogue charger that is based on the ESP32 interfacing through `12VFB` and `LOAD_SHARE` etc. A digital one based on i2c interfacing using an ESP8266. The ESP32 seems to have issues with i2c stability, and the ESP8266 have limited analogue interfaces.


# Background
The DPS-1200FB is a very powerful and compact powersupply. It can supply up to 100A adjustable between 11.8v-12.8v. This is perfect for supplying high currents to 12v equipment like your boat fridge etc. It won't, however, charge any 12v lead-acid or lithium batteries. You would need 14.4v (lead acid) or 14.6v (lithium) to get a full charge. There are some mods floating around on the interwebs on how to increase voltage, how to series connect two PSUs and how to amputate the Over Voltage Protection (OVP). 

# Goal
The goal with this project is to use an Arduino to control the PSU. Ideally you would be able to control output current, voltage, fan speed and on/off. That would allow us to build a powerful lab power supply, a custom battery charger, a flexible mining PSU etc etc. Should I not be able to reach the goal of controlling the PSU digitally through its data port, workarounds might be available.

# How
The PSU has an i2c port through which it reports status and takes commands. It contains two devices that responds on the i2c bus, the EEPROM and the PIC micro processor. Their addresses are set by the server by pulling up or down certain pins in the end connector. The EEPROM can be read and written using this bus. The MCU responds to commands sent to it. raplin (https://github.com/raplin/) has shown that it accepts fan speed commands, and reports fan speed back if queried. He has also documented several other commands and data.

## Connection
The PSU has a double sided edge connector. The majority of which is taken up by the high current output tabs. There are also 6 smaller tabs on each side. These have various functions in turning on the PSU and selecting its i2c address.

![Connector-bottom](https://github.com/slundell/dps_charger/raw/master/doc/images/connector-bottom.jpg)
The bottom part of the connector has pins 1 to 32.

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Fosterqc · June 4, 2020, 12:55am

sorry I should have edited, I was hoping to charge and ride

I should get a power supply like that thanks for the reminder.

Silverline · June 5, 2020, 9:39am

Can this pack handle 200amp load?

Fosterqc · June 5, 2020, 1:01pm

Nah lol wasn’t it like 40A max. Just ordered that buck converter so hopefully it works.

Scepterr · June 5, 2020, 5:05pm

45 iirc, has a 60 amp fuse

Silverline · June 5, 2020, 5:49pm

Thanks guys

PrivacyDoctor · June 7, 2020, 12:25am

You could also just remove one cell and directly connect it (at similar charge level, ofc)

Fosterqc · June 7, 2020, 12:30am

Good idea, I forgot about that.

I might want to use the same setup on a 13S board so it would be good to keep it 13S.

PrivacyDoctor · August 2, 2020, 7:17am

Did anyone buy one of these and didn’t end up using them? I would be happy to buy it from you.

Fosterqc · August 2, 2020, 3:40pm

STAY AWAY FROM MY CHEAP BABY

PrivacyDoctor · August 2, 2020, 4:18pm

I’ll pay for your baby’s shipping

Fosterqc · August 2, 2020, 4:20pm

This used robutt battery is kinda the the preserved shit of some prehistoric animal.

It’s priceless now

PrivacyDoctor · August 5, 2020, 6:37am

I just hacked mine:

But now I have the same issue as you had - Controller switching off after a second or two.
I wish I had read your post before doing all this work.

Now I wonder if I am better off bypassing the BMS or trying to add a second switch. How many amps were you able to pull through the BMS?
Did @Scepterr have success with discharge through the BMS?