Propel BB-590 Battery Charger

Poor Workmanship

I bought this charger on eBay (j5w23)and it came in a box marked "New BB-590" and the charger was wrapped in plastic, line cord has tie wrap, no marks of use and does in fact appear to be new.

The hand soldering is probably why these are on the market and/or that the BB-390 has replaced the BB-590. Mine had an open circuit between one of the charging wires and the banana jack and also had the 110 VAC switch wires routed through a hole in the chassis with sharp metal edges. I resoldered the four charging cable ends to the banana jacks and removed the two brown wires from the metal and resoldered them to the power switch.

Make these changes prior to using the charger!

Different units with Same Model Number

There are at least two different units, both marked Model BB-590.
The one with the 1702 smart charger ICs does NOT have the south plainfield NJ under the Propel at the top center front panel. If the front panel label includes "SOUTH PLAINFIELD, N.J." then the charger is NOT the smart one. I have not tested the South Plainfield model and so don't know if it's also a "Burp" charger or not.

Description

This is a Charger & Discharger for the BB-590 Ni-Cad battery or any 20 cell Nickel chemistry battery like my 5590BA Battery Adapter. It can independently charge or discharge two batteries at the same time. The charging is done using a patented pulse method rather than a DC current. Only two wires go to the battery wired positive (white) to pin 4 and negative (black) to pin 2. In the battery connector pin 1 is jumpered to pin 5. The charging battery plug is a 5 key slot type and so could be plugged into a primary battery like a BA-5590. It would have been better to wire the plug using pin 3 as the negative (black) , jumper pins 2 and 4 and use pin 5 as the positive (white), this way the charger could not charge a primary battery.

The "test" banana jacks on the front panel are wired in parallel with the battery positive and negative terminals.

The heart of this charger is a couple of the Galaxy Power ICX1702 ICs.

BatteryPlugs are Amphenol 10-101980-128 back shell and 10-588002-20 hermetic plug. There are very expensive in any quanity.

CBD

COMMERCE BUSINESS DAILY ISSUE OF NOVEMBER 25,1996 PSA#1728

Defense General Supply Center 8000 Jeff Davis Hwy Richmond, VA 23297-5312

61 -- CHARGER, BATTERY SOL SP0400-97-Q-Q164 DUE 120496 POC Contact: for copies of RFP/IFB solicitations (available at least 15 days from announcement, for copies of RFQ Solicitations, contact the buyer: Myra Sevrt/ZY187/804-27 9-4286. PR-NO: FPG96302001922

NSN 6130-01-182-1557, charger, Battery. propel Inc. P/N bb-590.
36 -EA Del to Mechanicsburg PA 17055-0789 Del by 24 Dec 96. 59 -EA Del to Tracy CA 95376-5000 delivery 120 days ARO.
Incremental quantities: min: 95 max: 209.
All responsible sources may submit offer which DGSC shall consider.(0326)

Operation

Charging

When a battery is installed the Galaxy IC does a soft start and then uses the patented pulse charging method. When the fast charge (FULL LED) mode is terminated it switches over to a topping charge (Trickle LED) and when that's done to the maintence charge.

When the trickle LED turned on after charging 20 Ni-MH cells in the 5590BA the box was not even warm. This took about 2 hours.
The next morning after "Trickle" charging all night the battery voltages are: 14.14 & 14.05 Volts for a total of 28.19 Volts (20 cells).
Next a PRC-104 discharge test. WOW!

The run time came in at 6.2 hours, way better than the Maha C777+ using the same batteries. The test is terminated with the voltage goes below 20 Volts (which usually is with the 1.5 amp load) so when the Open Circuit Voltage is checked shortly after the test it's around 24 Volts.

Connecting 20 new 1.0 AH Ni-Cad cells starting off at 26 volts, switches to trickle charge in about 4 hours with the battery voltage pulsing around 29 to 30 Volts. The Ni-Cads are slightly warm (about 95 F). Putting some different new Ni-Cads on the Maha C777+ has a much different result.
First try - charger stops after about 10 minutes saying the batteries are charged and only a small amount of charge has been added.
Second try - similar to the first try.
Third try - about 1 AH is added (the full capacity rating is 1.0 AH).
So the "Soft Start" in the Propel patent really seems to work in the Propel charger.

Using 22 cells in the 5590BA

Since this charger terminates charge based on the shape of the voltage vs. time curve it should charge a 5590BA when 22 cells are used. After charging the terminal voltage is about 30.3 volts with a 100 ma load. This morning (2 May 2005) see what capacity is in the cells by using the 1/2 PRC-104 discharge cycle. The run time is 7.8 hours, and since using 20 cells charged the same way using the Propel charger gave 8 hours, it appears that the Propel is NOT properly charging a 22 cell string.

Note that chargers that use charge termination methods that are not based on a fixed voltage should charge 22 cells. This could be a simple charger that operates with a constant current or a smart charger.

Discharging

The data sheet for the 1702 indicates that it can do both smart charge and smart discharge. This includes automatic battery connect sense for either charge or discharge. Switching to DISCH. and then plugging in a battery with a terminal voltage of 24.7 V causes the Trickle LED to flash. The battery voltage is being pulse loaded (the voltage is jumping between 23 and 19 ). In a few minutes the Trickle LED turned off and the battery voltage is a steady 24.37.

Next these same batteries that were charged using a lab supply will be charged using the Propel charger to see if it again gets more from theexact same cells. Gave about the same result 4.7 hours for Propel and 4.8 hours for lab supply at 300 ma.