5590BAv2 Battery Adapter

© Brooke Clarke 2007
5590BA ver 2 with 14 AWG crimped wires

5590BAv2 Inside view

Background
Inside Dimension Comparison Ver 1 vs. Ver 2
Power Pole Socket Option Idea
Battery Options
    Tested just after charging


Background

This is the second battery adapter made for the BA-5590/U family of military batteries.  The battery consists of two independent "12 volt" batteries and the load can be wired to connect them either in series for a "24 volt" battery or in parallel for a "12 volt" battery.  The first 5590BA battery adapter was designed using 0.060" thick aluminum.  And these was no planning for the use of Sub C cells so it's difficult to get 20 SC cells into the first version.  Version 2 holds 20 SC cells close packed with a little extra room on all sides.

The lid attach method on the first version depended on bending parts of the lid inward to act as fingers that mate with slots on the sides of the main box.  The combination of the stiffness of the 0.060" aluminum and the length of the fingers made it difficult to remove the lid.   Version 2 uses 0.050" aluminum so the sides are more flexible and the inward pointing fingers have been replaced with what's called a lance.  This is similar to a punch that moves the metal about it's own thickness and leaves the punched metal attached.  Thus the new  "fingers" are much shorter making for easy lid installation.

The overall dimensions meet the 5" x 4.4" x 2.45" plus zero minus 1/16" outline of the BA-5590/U and the socket is where it's supposed to be so it's a form and fit replacement for any of the BA-5590 family of batteries.

30 April 2008 - top photo (above) shows 12 AWG wires with crimped connections.  They measure 1 milli Ohm including the Power Pole terminal and the socket pin.  For more see the HP 4328A Milliohmmeter web page.

Inside Dimension Comparison Ver 1 vs. Ver 2


Ver 1
Ver 2
Delta
20 SCPack 0.9"
High
4.729
4.876
+0.147
4.798
Wide
4.250
4.278
+0.028
4.050
Deep
2.245
2.335
+0.090
1.930

Power Pole Socket Option Idea

5590BA Power Pole Idea28 Oct 2007 - Boxes back from laser marking.  A pair of power pole connectors will pass through the wire clearance hole below the socket.  If there is enough slack in the battery pack wires they could be threaded through the hole one pair at a time then coupled into a 4 terminal block.  The blue support blocks could then be used to anchor the block of connectors to the existing bracket which would need a couple of holes drilled and a spacer between the connector block and the bracket.


If the blue support blocks are not used a 3/32" cotter pin passing through the hole in the connector block, going through a spacer and a single new hole in the bracket would also work.  The connector block would have some "wiggle" and that's a good thing since the connector should have some play.

Power Pole connector option for 5590BAv2The SC cells used in RC racing cars have the ability to run at 30 Amps so an option for this battery adapter may be (idea stage) to use a different socket bracket to support Anderson Power Products "Power Pole" connectors using contacts rated for 45 Amps.

Twenty SC cells in series would have a voltage of about 24.0 when empty and with a current of 30 amps would be delivering 720 watts!  The parallel configuration would be 12 volts at 60 amps for 720 watts!

That's a lot of power.

The DARPA Wearable Power $1,000,000 contest is asking only for 200 Watts max power, but they want about 2 kWhrs weighing no more than 4 kg (8.8 pounds).  With 4.5 AH SC cells the capacity of the adapter would be about 20 * 1.2 V * 4.5 AH = 108 Whrs far short of the 2,000 Whrs they are looking for.  They specified the two voltages as 10 to 16 VDC and 20 to 32 VDC.  This is interesting because it eliminates Li cell batteries that produce a little more and have been know to blow out some equipment (Javilin) that can not handle the higher voltage.

The version 2 adapter weighs 3 ¼ pounds with the 3.3 AH SC cell pack, maybe a little more with 4.5 AH cells.

To support the Power Pole high current idea the internal wires need to be 14 ga or larger. 
15 Oct 2007 - A sample of 14 ga wire is on order to see if it will fit the connector pin solder cup (the dimensions say it's a little too big).
14 AWG super flex wire in 5590 socket pin

22 Oct 2007 - The 14 AWG wire will work with the connector solder cup.  Wire on order, here in a couple of days.

If the regular socket is used it makes sense to use the heavy wire to minimize IR drop even when lighter loads are being powered.
The photo shows a two pair of Power Pole connectors where each pair is the ARES standard configuration, but they are stacked.  They way you could plug in two independent "12 volt" ARES loads or make a jumper cable to get 24 volts.  For some ham radio applications the high current output would support short transmissions where high current is needed.

Battery Options

SC Pack

11 Nov 2007 - The reason for my current focus on the high current performance is not so much that the load would be drawing huge currents all the time, but on the need to be able to supply a current higher than the average current for short periods of time.  Many devices have a startup power requirement that's considerably higher than their run current.  If the battery can not supply the starting power then it can't power the equipment.  Also by designing for the higher currents resistive losses are lowered for the lower currents.

1 Nov 2007 - The 20 SC pack made for the first version 5590BA has been refitted with 14 AWG wire and Power Pole connectors with 45 Amp contacts.  It drops right into the 5590BAv2.
A Triton2 Charger Discharger Cycler is being used to get this pack up and running since it's been sitting for many months.  The discharger can be used to evaluate how well another charger works with a limit of 3 Amps max.  The Amrel EL1132 can handle 300 watts, which at 28 Volts is a little over 10 Amp discharge current.  Testing at 30 Amps from 30 Volts requires a resistor of about 0.9 Ohms that's good for about 900 Watts.  Not easy to come by.

 5590BA 20 Cell SC pack made for 5590BAv1

This pack requires a height of 4.798" and width of 4.050" when 0.900" dia SC cells are used close packed.  You can see in the comparison table they will not fit in version 1 but have room to spare in version 2. 

The pack was made in 2005 and has been sitting for over a year.  Using the Battery Space charger then load testing there was almost no charge.  The old 18 AWG wires and 15 Amp Power Pole connectors have been replaced with 14 AWG super flex wires and 45 Amp Power Pole connectors.  Using the Triton2 charger in cycle mode produced these input and output capacities:

Cycle #
Charge
Discharge
% D/C
1
2917
2040
70
2
2873
2533
88
3
2872
2543
89
Not bad, still in spec at Nov 2007.

Next getting ring terminals to make test cable for Amrel EL1132 Electronic Load to allow testing battery pack using 45 Amp Power Pole connectors instead of the 10 Amp rated 5590 connectors.

Load Test 2005 SC Cell Pack

9 Nov 2007 - The test was done using the Power Pole connectors on the battery pack, not using the 5590BA socket that's probably rated for only 10 Amps.  Two sides connected in series.
I
V
Watts
1
26.18
26
2
26.0
52
3
25.75
77
4
25.5
102
5
25.2
126
6
24.8
148
7
24.5
171
8
24.2
194
9
23.8
214
10
23.6
236
11
23.3
256
12
23.0
276
13
22.8
296
14
22.6
316
15
22.5
3371
Note 1 - The EL1132 is rated for 300 Watts and at 337 Watts it started making beeping sounds, so no higher currents were tested.  The limitation is the tester, not the battey.

Using Excel to fit the V vs. I data gives the equation:  y = -0.2847x + 26.526 where the resistance of the battery and test wires is 0.28 Ohms and the open circuit voltage is 26.5 Volts.
R2 = 0.9932 is a measure of the quality of fit.  When this same pack was tested in the first version 5590BA (including the socket) with 18 ASW wires on the pack and 15 Amp Power Pole connectors the internal resistnace was 0.35 Ohms.  At 5 Amps in the old thest the voltage was 26.1, a little higher than this test.  Maybe the pack is older or not fully charged.  Will try again right after charging.

Tested just after charging.

I
V
Watts
0.1
27.9
3
1
27.7
28
2
27.5
55
3
27.3
82
4
27.0
108
5
26.7
134
6
26.4
158
7
26.0
182
8
25.6
204
9
25.3
228
10
24.85
249
11
24.5
270
12
24.3
292
13
24.0
312
14
23.8
3611
Note 1 - The EL1132 is rated for 300 Watts and at 361 Watts it started making beeping sounds, so no higher currents were tested.  The limitation is the tester, not the battey. 

When the I V data is plotted in Excel  equation for the points is:
y = -0.3186x + 28.153  R2 = 0.9935  Note the open circuit voltage is now higher, about 1.41 Volts per cell.
For an output voltage of 20.0 (where most "24 Volt" equipment turns off) the current according to the equation would be 25.6 Amps for these two year old Ni-MH cells.
20 Volts @ 25.6 Amps is 512 Watts for these two year cells rated 3.3 AH.  Twenty cells @ 1.2 volts would be 79 Watt hours so at 512 Watts would run for maybe 9 minutes.

Checking a couple of SC cell suppliers:

http://www.cheapbatterypacks.com/?sid=853305&pgid=loosecells&chem=NIMH
is showing Ni-MH: 4.5 AH cells $ 7.35 each and 2.2 AH $ 4.65
Ni-CAD: 2.4 AH @ $5.75 and 1.3 AH @ $4.35

http://www.batteryspace.com/index.asp?PageAction=VIEWCATS&Category=226
is showing set of 20 matched Ni-MH 4.2 AH @ $ 4.30, 4.5 AH about $8
http://www.batteryspace.com/index.asp?PageAction=VIEWCATS&Category=296
Ni-Cad: 2.1 AH @ $ 2.30

Battery Comparison 13 Oct 2007

Table based on user made battery pack.  i.e. neither labor to make pack included nor cost of misc links, connectors, wire, etc.
Make
Size
Chem
AH cap
$/cell
#
cell
Watt hrs
per pack
$/pack
$/Wh
ELITE4500 SC
Ni-MH
4.5
7.35
20
108
147
1.36
ELITE3600 SC Ni-MH
3.6
4.95
20
86.4
99
1.15
4200
SC Ni-MH
4.2
4.30
20
100
85.95
0.85
2100
SC Ni-Cad
2.1
2.26
20
50.4
22.95
0.46
10xAA (4 packs)
AA
Ni-MH
2.2
2.60
40
106
103.80
0.98
2600 (in b. holders)
AA
Ni-MH 2.6
1.43
20
62.4
28.60
0.46
LS91 (in b. holders) AA
Li-FeS2
3.0
1.97
20
72
39.35
0.55


The 5590BAv2 may be sold as the box with secondary style socket terminated with short super flex 14 AWG wires terminated with a pair of 45 Amp rated Power Pole connectors (4 terminals) in standard ARES configuration.  And also offer optional battery packs.

20 SC Cell Packs

Packs are made using either spot welding or soldered copper link bars.  The table above shows only a few of the SC cells that are on the market.  Since the 0.9" diameter cells easily fit ver 2 commercial packs can be made without custom fitting.  The SC pack I made for version 1 just drops in with room to spare.

An interesting prospect is the ability of delivering 30 amps at 30 volts or 60 amps at 15 volts, i.e. 900 Watts.  The cells and wiring are up to it but I don't know about the connector.  I've heard that each contact can handle 10 Amps, i.e. good for delivering 10 A @ 30 V or 20 A @ 15 V for 300 Watts.

40 AA Adapter

This would be an adapter that can hold 40 AA cells.  It allows the use of Alkaline, Ni-Cad, Ni-MH, LiFeS4 (Energizer L91 1.5 volt Lithium), Sanyo eneloop Ready To Use (long shelf life) Ni-MH, or whatever new chemistry comes out in the future.  AA cells typically are where the newest technology shows up first.  Short wire leads with Power Pole connectors.  A string of 10 cells gives 15 volts so 20 cells is the number needed for the two sides to the 5590 family battery.  So you could install just 20 cells or for more capacity install all 40.

I'm investigating the eneloop Ready To Use Sayno AA cells.  They claim a much longer shelf life than other Ni-MH cells.  This is being done with a Maha C9000.

CR123 Photo Battery Adapter

The same idea as for the AA adapter, except for the CR123 photo batteries.  These are 3 volt cells so a string of 5 gives 15 volts so 10 cells is the minimum number to have a working 5590 family battery, adding multiples of 10 cells to give 20, 30, 40 or maybe 50 cells adds capacity.

Links

back to Brooke's: PRC68, Battery, BA-5590/U Family, 5590BAv1, Battery Patents, Military Information, personal home, Alphabetical list of web pages 
page created 15 Oct 2007