Dumb Battery question 101 (it's the connectors dummy!)

First I'd like to say "great forum." A Mechanical Engineering friend told me about ES years ago, and, here I am with my first dumb question!

I have a couple of Razor EcoSmart Metro Electric Scooters and it's "battery changing time" again (actually my first time.) I matched battery specs: 12V 7AH, of the original factory batteries. My soldering iron was not "up to snuff" to remove (what I believe is) the silver solder, of the factory soldering.

So I hit upon a solution, for convenience, but the performance after, was problematic. I pretty sure it's the connectors, because, why would anyone do it different if it were that easy? Besides durability due to vibration, corrosion, etc. I haven't added the tin solder and silicon gel, for weather insulation. I add a picture for simplicity, and a technical description if that fails.

PROBLEM: replaced factory silver solder on battery terminals with 12-10 AWG Disconnect F clip connectors and performance is "sketchy." I have not added any tin solder to the tab/connector point nor tinned the wire, before crimping. Nearly fried my Fluke Mutimeter in attempting to measure DC amperage (it's been a while since I did anything electrical, of a battery nature, but I have the wherewithal to do it right, going forward

https://drive.google.com/file/d/1_fG5p2vT2ZrubIu1ZGVDa5zUMzmuJnm1/view?usp=sharing

I've had issues with those connectors carrying high amps, they just don't seem to keep their "grip" when they heat up, and a bit of vibration seems to wiggle them loose. You might try tinning them with solder (doesn't need to be high silver, they shouldn't get that hot, nor have alot of mechanical stress on them).

Also, your Fluke meter should have a fuse in it, if you blow it measuring too many amps you can replace it.

BAGGAB said:

PROBLEM: replaced factory silver solder on battery terminals with 12-10 AWG Disconnect F clip connectors and performance is "sketchy." I have not added any tin solder to the tab/connector point nor tinned the wire, before crimping. Nearly fried my Fluke Mutimeter in attempting to measure DC amperage (it's been a while since I did anything electrical, of a battery nature, but I have the wherewithal to do it right, going forward

Click to expand...

OK. A few notes:

1) Soldering is not a good idea on any connector that will see regular flex/vibe (like most connectors on ebikes/scooters.) Soldering concentrates the stress on the end of the solder flow, and overheated/broken wires is the result.

2) A good crimper will give you a great connection - low resistance, mechanically strong, resistant to vibration fatigue. "Good crimper" is not the sort you buy in Home Depot, though. For example, for the Anderson Powerpole connectors (common ebike connectors) a good crimper costs between $40 and $250 and is designed for those specific crimp terminals.

3) To measure current you really need a clamp-on ammeter. However, your problem is likely a high resistance connection. Compare the voltage at the battery terminals to the voltage at the motor controller under load. If you see more than about half a volt, then your connections are suspect.

That style of connector is pretty marginal for a battery connection. If the connectors are properly crimped, you should have a good connection between the wire and the connector. Between the connector and the battery terminal is where you tend to have problems. Those things need to be really tight and they loosen every time you unplug them. I have used pliers to slightly bend them to get a tighter fit.

You could solder them after pushing them on the battery terminals to keep them from vibrating. That's what I've seen on scooters like that before. Too much heat on the battery terminal can damage the battery, so you need to keep heating time short.

Next time they die, you should consider changing to lithium batteries. Much better range, less weight, and they can last over 10 years with proper care.

FOLLOW UP:

fechter, yes, my next move is to tin the wires and re-crimp. Then, use silver solder to attach the clip. When you say "heat" you mean some heat transfer through the battery terminals to the battery chemistry; that's good to know. Lithium batteries are now being considered and I'll explain below.

billlvon, I'm gonna fill the trough, formed between the F connector curling, with silver solder. I turned them upside down for that purpose. It's probably not going to work well, but I'm approaching this incrementally. I kind of implied that this wasn't going to work, when I said that manufacturers would be using them, if they could. The batteries are a new set and I don't know what they are "quality-wise," but they have the same rating.

I would like to get to Anderson Powerpole connectors, I need to know more about them, so thanks for pointing them out. If you have a favorite crimping tool, please let me know. This is a learning experience and purchasing becomes a commitment to that tech. So far I haven't spent much, but I do like to buy quality tools. What I really need, right away, is that clamp-on ammeter and I'm looking for suggestions there. I need to order that tomorrow.

You comment # 3) is good info, as I need some quick testing. I jumped into this because the batteries were reaching the end of their usefulness. My Fluke has a 10 A fuse, and I was aware that it was fused, but I was acting in haste. When the meter wires got hot in my hands, I knew I was acting like a dummy around electricity. I use this scooter to commute 10 miles a day and I didn't want to get back on my pedal bicycle, so I was rushing the process.

PHILOSOPHY:

I gave up my car and started riding a bicycle 13 years ago, for environmental reasons. I noted that not much was happening to deal with Global Warming, so I decided that I was going to back off my activism. So, I've been wanting to electrify my bicycle for a while.

I picked up a Razor EcoSmart Metro, new, and a second at a yard sale, for parts. I got into these scooters as a testbed for learning about electric motors and batteries. I was told that you can destroy Li-ion batteries, and I wanted to know more about motor torque rating, as it compares to my commute route.

So I have three units to develop into reliable transport, using Li-ion. That's the goal. I hope to make some how-to videos for the next person, along the way. There are many videos out there, but, so far I don't see the type of video I want to do. I'm keen to get people on electric vehicles at low cost.

Thanks dustNbone and everyone for the replies. I mixed up, who I was replying to, in getting back to you. I find myself a little "fried" after working on some computer networking issues, unrelated to this forum discussion. So, I'm a little distracted. But laziness, is the mother of motivation.

I just don't want to peddle my bicycle anymore

Picked up a GREENLEE CM-660 Clamping Meter. [strike]Pretty happy all around.[/strike] Ok, I'm not happy.

I looked over forum rules and I didn't see anything about mentioning brand names, so I am forging ahead. I do not sell any of this stuff and I have a lot of respect for manufacturing (all aspects of the supply chain.)

Went to Jerry's (a Home Depot type local retail chain.) I conferred with my Electrical Contractor friend, as we examined the ammeters available. He mentioned GREENLEE as a product line used in the industry. I got the CM-660, as a low-end, "get the job done," CAT IV* ammeter. Nice product, but not up to what I need, and can I grump here? The packaging covered the complete series: CM-660, CM-860, CM-960, CMH-600, CMI-600. I needed the AmpTip (TM) for DC current; which is offered in the CM-960. So, back it goes! I hate to return stuff, but I do buy a lot of stuff from these folks, so I'm Ok with it, this time.

So, listen to the guy who told you "not to shop at Home Depot" and get the high-end.

After reflecting on the subject, I felt the purchase of a high-end product would be justified, as I am going to tinker with robots and Raspberry Pi's down the road.

* REF: http://www.ni.com/white-paper/5019/en/

Ok, this reply post deals with Li-ion batteries. The problem is theft. Here in "oh, so groovy," College Town, Eugene, OR, bike theft is a huge problem. I'm sure it's a problem in your area also.

It's part of the reason why I've been slow to implement Li-ion. I have realized that I can replace the Li-ion on the Scooter and none will be the wiser. I am now looking for battery brand suggestions (hopefully the one's you use.)

Re-posted in the Battery thread.

BAGGAB said:

I would like to get to Anderson Powerpole connectors, I need to know more about them, so thanks for pointing them out. If you have a favorite crimping tool, please let me know.

Click to expand...

I have had OK luck with the cheapest crimper they sell on the Powerwerx website - the TRIcrimp. It will crimp contacts for the 'small' Powerpole connectors - the ones good for up to 45 amps. There are three contacts for those connectors - 15, 30 and 45 amps. Each type of connector has a separate tool on the crimper. It takes a little practice to use it.

Thanks Bill (billvon,)

I'm pretty much "lost in the woods" at this time. I've decided to go forward, and today I'm going to replace the ammeter, for a better one. I'll be getting back to you after I've done some reading and research.

I have three transports to MOD: two scooters and a bicycle. The bicycle has a unique frame type, called an "easy boarder," that could present some problems with cable length, etc. I am also, looking to hide the battery, for considerations of theft, but I'm probably looking at a modular system where I can detach the battery and take it with me.

I'm not as concerned about range, as I am about convenience of use. It has to be all year, all weather, and if I can make it "sexy," you know, so people look and possibly learn, about electrics.

After this misstep, I'll want to buy a high-end crimper that can support a variety of crimping jobs. Later, I will be getting into robotics as an education platform.

So a quick check on the powerwerx website shows the Tricrimp at $39.99. That's not going to "break the bank."

Brian

I purchased the Anderson Powerpole Connectors (APC) starter kit, which comes with the TRIcrimp and an assortment of 15, 30, 45 amp contacts. That should arrive in a few days. My understanding of these APC are that they are designed for a round wire. Is there a special APC that is used to connect to the flat tab of the battery terminal? Something that I neglected to order?

I'm looking for verification. The 15 amp connector can be used to crimp directly to the battery tab type connector or do I need a short wire lead soldered to the battery tab connector, then the APC is attached to that lead? The wire is 16 gauge and that implies using the 15 amp connector or should I use a higher rated connector?

Any advice is greatly appreciated!