Range problem - fairly new batteries

I just picked up a lifted e825 last month, with fairly new trojan 30 XHS batteries (aug 2014 per date codes), and I can only eke out about 7-8 miles on it before things die.

When fully charged using the built-in charger, all batteries read within .01-.02 of each other (don’t recall the exact voltage - 12.7ish?). When the car says it’s time to recharge (gauge <005 and audible alarm), the batteries read from 12.38-12.48 (batteries 1&4 read .48, the others read .38).

That seems really high for dead batteries to me - and really close to the starting voltage. Does that sound right?

What should I be looking at next?

Oh yeah, water levels and hydrometer readings are good across the board.

JAT but batteries connected correctly + to - across the board (±±±±±±)? Total pack should present 72+v anything less suggests one might be installed “backwards” (e.g. ±±±-±±±).

Also check hydrometer readings on all 36 cells after charging and again after it’s “died”. One of the cells could be bad - voltage itself is not a reliable predictor of “goodness” IMO. Voltage and hydrometer reading is much better indicator. Doesn’t take many dead cells to pull down the whole pack since they’re all in series.

[quote=ARandall;24564]JAT but batteries connected correctly + to - across the board (±±±±±±)? Total pack should present 72+v anything less suggests one might be installed “backwards” (e.g. ±±±-±±±).

Also check hydrometer readings on all 36 cells after charging and again after it’s “died”. One of the cells could be bad - voltage itself is not a reliable predictor of “goodness” IMO. Voltage and hydrometer reading is much better indicator. Doesn’t take many dead cells to pull down the whole pack since they’re all in series.[/quote]

Just tested all 6 batteries with a load tester as well and no problems. I’ll check the hydrometer readings again in their current ‘dead’ state, but given that the pack is reading >74V and the cart says it’s dead, I’m wondering if I’ve got a non-battery related problem?

74.28 volts is 70%. Doesn’t sound right. Check what Al said.

You said lifted cart. Please be a little more specific. Wheel and tire size, motor HP, Transaxle ratio, flat or hilly terrain, and any other differences from stock. Raise each wheel, they should spin free.

[quote=OLD HOUSEBOATER;24567]74.28 volts is 70%. Doesn’t sound right. Check what Al said.

You said lifted cart. Please be a little more specific. Wheel and tire size, motor HP, Transaxle ratio, flat or hilly terrain, and any other differences from stock. Raise each wheel, they should spin free.[/quote]

I’d love to be more specific, but other than the fact that it’s lifted, I’m not aware of any other work done to it. This is all on completely flat roadways - i’d be shocked if there was a 50ft elevation change total in the 7-8 miles I drove it.

The hydrometer readings all came back normal - I’ll check the wheels next…

If you’ve tested all the batteries voltage and specific gravity before and after your range problem and everything tested normal I think you’ve eliminated batteries as the problem.

Unfortunately I can’t suggest anything else obvious to account for the symptoms you’re reporting. Maybe controller or wiring issue? Don’t know how the controller senses turtle mode except probably low voltage which suggests a wiring issue or controller problem to me since you’ve eliminated battery issues.

Check all connections for bright and tight. Read overall voltage not individual. Your system is looking for 74/ 78+ volts not 12 volts six times. one corroded connection can do the dirty work. What size wheels and tires do you have?

You make a very good point. 12v (x6=72v) is “nominal” but the reality is higher. Good solid connections do matter. Good advice to check the connections. While I had everything off, I’d brush off the lugs and terminals to eliminate any corrosion, tighten it all back up and spray with “corrosion protection” stuff to eliminate that as a source of future problems.

Updates - the tires are ATV tires AT25x10x12. The motor appears to be a bone stock GM 5hp motor. The Charger is a Zivan that has been upgraded/flashed and programmed for flooded cells. The motor controller appears to be a T2 (those are the last 2 digits of the big long ID number on it)

All 4 wheels spinning freely as well.

At the main contactor, I am getting 74.6-74.7 volts when ready to run (key on, parking brake down).

Here’s the weird thing - today the BDI says 75%, but it hasn’t been charged since it alarmed and said 3% yesterday. Maybe I’ve got a bad battery that needs a little more load than my load tester can generate to show as bad?

I’ll drive it some more later with the multimeter hooked up to see if anything reveals itself. If that doesn’t work I’ll do laps around the block with the multi on each cell individually to look for a really low one.

Thanks so much for all your help guys.

Question - if it does turn out to be 1 or 2 bad batteries, do I need to replace them all at this age (9-10 months)?

Eureka! So it turned out that driving with the multimeter on each battery was critical to finding this. Within 1 minute of stopping, the bad battery would read the same voltage and hydro as the other ones, but while driving it dropped several volts below the others, before finally quitting entirely. It’s like it shorted and just dropped out of the pack completely - read 0 V until things were stopped and shut down.

So now I have one battery that craps out after 5-8 miles, and the rest seem to be good. Do I need to replace all 6 at once? Anything that could be done to restore the bad one, or is it just toast?

At 9 or 10 months, I probably wouldn’t replace all the batteries, only the failed one(s), especially if they’re Trojan.

At about $200/each, you’ll want to be 100% certain it’s a failed battery and not something else. Sounds like you’ve got it well in hand. Trojan may even replace the bad battery under warranty.

Incidentally you’ve now made me a believer in BattSix with what you just reported since that’s exactly what BattSix does by monitoring voltage of all 6 batteries at the same time.

Al

First look to see if the batteries have a warrenty. My batteries charge up to 78volts after each charging. I had a charging problem and could not find out what the problem was. I was even dumb enough to have the local dealer check it out. They said everything was perfect. I then installed a BattSix system. I could then tell I had a bad battery. I replaced that battery only. That was several years ago. The batteries were 3 years old then. At $300.00 per battery(gel) I couldn’t afford a whole new set. Some will tell you that, with great reasons, you should change all of the batteries at the same time. Others, including fleet owners, will tell you that since the batteries are new enough you can just change out the bad ones. Having sold batteries in my past, it is possible you could have more than one bad battery. Good luck Barry Chico, Ca.:bullettrain_side:

I would suggest going back through every connection to make sure they are all tight. So far every time I have a quick battery usage or overheated motor its been due to loose cables and they will loosen over time. Check the connections on the motor, controler and blocks also. If the batteries are the age you stated then they should still be under warranty.
Good luck

Yes, the batteries are probably under warranty, but they’ve been through a few hands since purchased, they were purchased online, and the guy who originally bought them doesn’t have the records or remember where he got them…

I found a local golf cart shop that got me a replacement for $175, so I should be good to go - taking her out for the first 7 mile test drive today.

PS - Yes, I checked all of the connections - everything is tight and bright.

It doesn’t matter where you bought the batteries or from who. Take them back to a Trojan dealer. They should warrenty them back to the date stickers on the batteries. Barry Chico, Ca🚄