FIRE! no start P3006 - P3016 - P3030 - parts & install ECU + Wire Harness to Traction Batt

Those modules are dead. They are sealed, you cannot add any fluid.

Time to figure out how you are going to fund 38 replacement modules.

 

Why can't the battery be grid charged? Is it really that dead? Is it worth a try?

 

If they have lost significant water, Bob has found experimentally that adding distilled water can help - but he hasn't found any effective way to reseal them after adding it, so that's not a practical procedure at this time.

At an RC-hobby store you should be able to find smart NiMH chargers that you can program to recharge your modules safely. Here's an example that's actually 4 such chargers in one box, allowing you to do your 38 modules in a fourth of the time. As Patrick suggests, you might not get satisfactory results with the modules in that condition. I might try charging some of them anyway....

-Chap

 

Fire makes smoke which condenses on every available surface. There it absorbs water from the air and becomes a resistor. In effect, the modules have self-discharged. When folks talk about 'fire damage,' it is really smoke that settles and corrodes every exposed, metal surface. The risk is the low voltage modules MIGHT get a reverse charge and that kills them!

I plotted the voltages and would not call those modules 'dead' until tested but two things need to happen pretty soon:

1. disassembly of modules for cleaning, mark top of each with a permanent marker with their position number OR record the serial numbers on top
2. put a minimum charge on the modules to get the voltage up to the 6V range

Find a place where the modules can sit apart and safe during the salvage charge. Wash each with water and dry. Put them side-by-side in three groups with all positive terminals on one side and negative terminals on the other in the following groups:

• 3-4V group
• 4-5V group
• 5-6V group (anything over 6V, keep isolated)

Wire all of one side terminals together with bare, copper wire, 18-22 gauge, for each group. Keep each group electrically separate. Starting with the 3-4V group, slowly wire the other terminals together but wear thin, gloves as the wire can get hot. In effect you are make three groups of modules wired in parallel. The weaker modules will take charge from the stronger ones . . . for now. The 5-6V group is the one most likely to get hot enough to burn.

Using three separate, 6V chargers, start charging each group with a target rate of 1A each. If you only have one charger, start with the 3-4V group first, at least 24 hours. Then the remaining groups. You want to get them up to 6V and keep the three, parallel groups isolated until they are at or close to 6V. This initial, parallel charge is part of a survey to find out if the modules are even possibly serviceable.

We need to know if any of the three groups holds a charge or has one or more cells within a module so discharged they can not recover. So note the date and time the charger is taken off a group and then measure the voltage some time later and again, record the date and time. If one or more groups drops 1.2V within an hour, there are unrecoverable modules in that group.

About battery chargers, especially automotive, they have almost no regulation. What this means is their "6V" is really not terribly accurate. Many are nothing more than a transformer and rectifier with no other regulation. Wall-wart power supplies are often just as bad. We do not want voltages on the battery groups to go over 7V at this point because they can internally form gas and expand . . . badly!

Once you get the first group on a charger, time to wash and dry the base and cover. The problem will be the control electronics area. This is one area where water is not going to be 'a good idea.' But it is important that all residual smoke get removed. Perhaps some of the others may have some ideas on smoke removal using a non-water based, wash.

Remember I mentioned GOOD, FAST, CHEAP, pick two . . . FAST is no longer an option and even GOOD is sounding marginal because of the smoke. You are looking at about 2-3 weeks before reassembly can begin.

Assuming all three groups reach 6V and can hold it for 24 hours, it will be time to wire them all together in parallel including the modules that were previously held aside. Then you will need to put them on a regulated charger and bring them up of ~7.2-8.0 V. This last, parallel charge will put the modules at as close to the same state of charge (SOC) as can be practically achieved. But this does not mean they are good.

Batteries have an Amp-Hour capacity, the amount of charge they can hold. Parallel charging just brings them up to a voltage level close enough that they have a chance of being used. The Amp-Hour (Ahr) capacity is measured on a module-by-module basis by charging them up to a given level and then putting a known load on a clock to measure how much electrical power, the amps, the battery can return. My experience:

• <1.5 Ahr - useless, they will take a small charge quickly and discharge just as quickly
• 1.5-2.5 Ahr - only if there there is no alternative and the others have similar capacity
• 2.5-3.5 Ahr - Ok, it can work
• 3.5-5.0 Ahr - Nice, still needs to be a matched set
• 5.0-6.5 Ahr - Very nice! Almost new!
• >6.5 Ahr - check your instrumentation, something is wrong

The art of measuring the Ahr capacity takes time, measured in weeks because there are 38 modules. This is important because when reassembled, the weakest and strongest modules need to be paired. Then the strongest pairs need to be put in the center and weakest pairs on the end.

Bob Wilson

 

I simply used Shoe Goo when I cleaned up my last two batteries. It worked great.

I think that the OEM sealant was acidic and galled the copper bus bar. For that reason alone I did not re-seal the bar with it.

 

Nope, Shoo Goo is toluene and solvent naphtha. From my experience it stays quite pliable. You can go HERE and read it's MSDS.

 

For $50, it seems to me to be a bargain. I wold have done that if I had the opportunity.

 

The battery was originally designed to be assembled without sealant. The later model batteries with the improved modules are assembled without sealant. The 40G sealing campaign was a one-off repair ritual that got invented for this battery when they noticed some of the modules could leak early in the battery's life.

The 40G repair, applied early in the life of a battery that was young and in otherwise great condition, made sense. The modules were all good and healthy, the battery would probably last many more years without any repairs needed, so who cares if adding this sealant makes it a PITA to work on down the road?

Think how much less of a hassle this repair would have been for you without sealant. You wouldn't even have needed acetone.

Your battery isn't in anything like the same circumstances as back in the day when the resealing campaign made sense. It's 12 years old now. The modules have been ridden hard and put away wet, not to mention soot coated. Their capacities are diminished. If you've done a good job of cleaning, you've probably pushed any P3009 problems far into the future, but even if all 38 of your modules come back up to usable state as you charge them just now, some of them might be borderline enough that you'll be returning in the next few years to replace some of them. Will you really want to have to deal with sealant again?

-Chap

 

What rate, amps, are you charging them with?

Each NiMH cell in the six-cell modules is rated at 1.0-1.2V nominal charge. They can briefly peak out at 1.33V BUT there is a risk of gas formation. The tell of a fubar module is being down 1.2V compared to the others. That lets us know at least one cell has died (and they don't come back.)

There are two well known failure modes:

• heat - there is a plastic 'mesh' separator between the + and - sides of the battery. If (when) it dries out, the current is concentrated in a smaller and smaller spot until it melts a hole in the plastic mesh. That shorts the cell and it is unrecoverable.
• reverse (or very low) charge - the NiMH (Nickel Metal Hydride) cell works by stuffing hydrogen into the metal matrix. This requires the surfaces to be properly 'prepared' and the rare earth metals to still be in the matrix. A reverse charge 'kills' the surface and too low charge and some of the rare earth metals will leach out of the matrix, also killing the cell.

The Ahr capacity I mentioned earlier is a measure of how well the metal hydride can still accept hydrogen. IF the cell is not failed, adding water and about 25-50 cycles will restore the cell to original capacity. I was dumbfounded to see that happen. But I could never figure out how to seal the hole and my plastic welding experiments were not successful.

The other aspect is to realize the Ahr capacity determines how quickly the voltage increases and decreases as the module charges and discharges. A weak module can be driven into a bad place and then fail hard. So it is very important to try an match the modules in Ahr capacity and then initial state of charge.

Bob Wilson