250W 36 or 42V charger/balancer for 100$

[flip_normal]

These are probably the cheapest/best deal available.

NEW - UNUSED 50V DC POWER SUPPLY 9.9A BY MINEBEA on uk ebay.


From the spec sheet :

3 Protection Circuits
In the case of over temperature or AC fail the PSU will restart automatically
The PSU is overload and continuous short circuit protected!
In the case of output overvoltage the PSU will latch off. There is no automatic restart.
It can only be restarted by cycling the AC supply.

So it seems they have isolated output and therefore 3 can be paralleled for a max of 29.7A @ 50V

Assuming your mains supply can deliver enough watts then these should do the job. They are high quality units.
There's a thread about them here.

BTW efreak I didn't mention adjusting anything down.

 

[efreak]

thanks flip these are good prices but shipping is murder $100CAN i ll keep searching i remember reading here
that when two of the 500 watt variety PS were parallel they showed a tendency to maintain their amp limit rather than putting out say 20 amps. i ll try to read that again i maybe have been mistaking Or Mis remembering.

efreak

 

[efreak]

that is what i am trying find out for certain . for example
http://cgi.ebay.com/400W-48V-8A-swi...goryZ296QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
this 400 watt would work for me if i was certain that these three can supply me with say 24 amps 48 v for my 10 modules

or there 500 watt or 800 watt sometimes it says that they are capable of 2 kw stacked .

if that can work i could go ahead and get them since they seem to be my best bet at the moment

efreak

 

[deVries]

A Great cheap charging solution!

250W balancing at 5A 10s charger for less than 100$

Buy:http://cgi.ebay.com/BTC-POWER-CONVE...ryZ36338QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

combine with: http://cgi.ebay.com/350W-48V-7-2A-S...ryZ20589QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


A little bit of DIY and you get a perfect charger!! I mean.. all cell ALWAYS BALANCED!!! cause it's 10 individual charger.!

Same principle as my DC-DC charger project!

Doc,

For example, let's say one has 16-4p packs. Is it possible to connect ONE isolated 3.7v DC out @ 100amps & divide it into 16 connections with equal length wiring to all 16-4p packs? So, each 4p pack would get juiced with 100a/16-4p = 6.25amps @ 3.7 volts per 4p pack OR about 1.5amp per cell.

Is this possible?

TIA

 

[ZapPat]

A Great cheap charging solution!

250W balancing at 5A 10s charger for less than 100$

Buy:http://cgi.ebay.com/BTC-POWER-CONVE...ryZ36338QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

combine with: http://cgi.ebay.com/350W-48V-7-2A-S...ryZ20589QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


A little bit of DIY and you get a perfect charger!! I mean.. all cell ALWAYS BALANCED!!! cause it's 10 individual charger.!

Same principle as my DC-DC charger project!

Doc,

For example, let's say one has 16-4p packs. Is it possible to connect ONE isolated 3.7v DC out @ 100amps & divide it into 16 connections with equal length wiring to all 16-4p packs? So, each 4p pack would get juiced with 100a/16-4p = 6.25amps @ 3.7 volts per 4p pack OR about 1.5amp per cell.

Is this possible?

TIA

No can do. Your cell groups are connected in series, so would would effectively short all your cells by doing this.

Only if you disconnect all 16 individual cell groups from their series connections, and reconnect them in parallel you could do this. It then looks just like one big cell... but who would be crazy enough to do this?

 

[deVries]

A Great cheap charging solution!

250W balancing at 5A 10s charger for less than 100$

Buy:http://cgi.ebay.com/BTC-POWER-CONVE...ryZ36338QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

combine with: http://cgi.ebay.com/350W-48V-7-2A-S...ryZ20589QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


A little bit of DIY and you get a perfect charger!! I mean.. all cell ALWAYS BALANCED!!! cause it's 10 individual charger.!

Same principle as my DC-DC charger project!

Doc,

For example, let's say one has 16-4p packs. Is it possible to connect ONE isolated 3.7v DC out @ 100amps & divide it into 16 connections with equal length wiring to all 16-4p packs? So, each 4p pack would get juiced with 100a/16-4p = 6.25amps @ 3.7 volts per 4p pack OR about 1.5amp per cell.

Is this possible?

TIA

No can do. Your cell groups are connected in series, so would would effectively short all your cells by doing this.

Only if you disconnect all 16 individual cell groups from their series connections, and reconnect them in parallel you could do this. It then looks just like one big cell... but who would be crazy enough to do this?

Thanks ZapPat... don't want to short anything... switching to another possibility...
Crazy... ? ->Could one set-up a series 'jumper plug' that when unplugged before charging all the series connections are open/unconnected. Then just plug-in the 'jumper plug' to reconnect the series wiring after charging? Same idea for the massive 4p16p parallel connections. Have all the 16p parallel wiring done into an open plug when not charging, and then plug-in the 16p parallel jumper plug 'to fuse' it into one massive parallel battery of 4p16p for charging with this amp-motherload below in pic. Put two of these in parallel for 200amps, yeah! baby...

And, I'm sure hoping there's a safe way to do this simply w/o shorting or melting things, (fuse or switch or plug/unplug jumper technique?) I hope. Can it work???

View attachment DC Converter.JPG

 

[ZapPat]

Thanks ZapPat... don't want to short anything... switching to another possibility...
Crazy... ? ->Could one set-up a series 'jumper plug' that when unplugged all the series connections are open/unconnected. Then just plug-in the 'jumper plug' to reconnect the series wiring? Same idea for the massive 4p16p parallel connections. Have all the 16p parallel wiring done into an open plug, and then plug-in the 16p parallel jumper plug 'to fuse' it into one massive parallel battery of 4p16p.

And, I'm sure there's a safe way to do this simply w/o shorting or melting things, (fuse or switch or ?) I hope.

You'll need a hell of a lot of switches - make yourself a drawing of each setup, and you'll see just how many!

Also, your switches used for your series connections will have to be rated at fairly high currents (each around what you'll using during your ride). The charging switches could be smaller, as long as each one is connected directly between it's cell group and the charger connections (meaning not in a chain connecting from one group to another).

I'm going to try another route myself, but similar to DocBass's DC converter method - I'm going to use one or two artesyn DC converters along with a bunch of relays to switch the low-voltage charging output(s) from one cell group to another. This reduces costs quite a bit, but I will have to write a bit of a program for a PIC micro to control this setup (not a big deal at all). Each DC converter costs 13$, and I've found good relays for about one tenth the price on ebay, so do the math... Good for people with a smaller capacity battery bank, and not wanting to invest too much for a good balancing charger. Also, no need for series disconnect switches in your pack with this - just taps coming out for charging between each cell group.

 

[deVries]

Thanks ZapPat... don't want to short anything... switching to another possibility...
Crazy... ? ->Could one set-up a series 'jumper plug' that when unplugged all the series connections are open/unconnected. Then just plug-in the 'jumper plug' to reconnect the series wiring? Same idea for the massive 4p16p parallel connections. Have all the 16p parallel wiring done into an open plug, and then plug-in the 16p parallel jumper plug 'to fuse' it into one massive parallel battery of 4p16p.

And, I'm sure there's a safe way to do this simply w/o shorting or melting things, (fuse or switch or ?) I hope.

You'll need a hell of a lot of switches - make yourself a drawing of each setup, and you'll see just how many!

Also, your switches used for your series connections will have to be rated at fairly high currents (each around what you'll using during your ride). The charging switches could be smaller, as long as each one is connected directly between it's cell group and the charger connections (meaning not in a chain connecting from one group to another).

I'm going to try another route myself, but similar to DocBass's DC converter method - I'm going to use one or two artesyn DC converters along with a bunch of relays to switch the low-voltage charging output(s) from one cell group to another. This reduces costs quite a bit, but I will have to write a bit of a program for a PIC micro to control this setup (not a big deal at all). Each DC converter costs 13$, and I've found good relays for about one tenth the price on ebay, so do the math... Good for people with a smaller capacity battery bank, and not wanting to invest too much for a good balancing charger. Also, no need for series disconnect switches in your pack with this - just taps coming out for charging between each cell group.

Thanks! ZapPat, I think your ideas are excellent and safer to use w/o the high amps, but I wonder if I can do my set-up without switches or relays using some plugging/unplugging techniques? After all, when connecting many parallel packs in series, to create the final battery in the first place, there certainly is a safe wiring-connections procedure to do this.

Here's a newbie question for any experienced battery maker... How does one create a completed battery and wire the series connections safely, in sequence, to connect to all the 4 celled parallel batteries? In my case I will have 16-4p "cells". We don't use switches or relays to wire in series from the parallel cells, so all one has to figure out is a way to copy this method in a more automated way that is still safe.

I think I should be able to avoid using switches or relays with some smart plug design techniques for unplugging the series/parallel connections and reconnecting.

Any ideas? ...I think the key is... How does one initially wire the series battery safely, in sequence, to connect to all the 4 celled parallel batteries to create the final battery? Also, is there a proper sequence for connecting the 4p cell-groups too... does one wire all the positives together first before connecting all the negatives together... or is it just the reverse? Or, flip a coin?

Since this topic of safety and wiring procedures is not thoroughly covered in its own thread, I'm going to move this part of the discussion to a new topic: Safe Procedures to Connect Disconnect Battery or Reconfigure ...here: http://endless-sphere.com/forums/viewtopic.php?f=14&t=5720