How does your team charge & test batteries?
 

I have seen a few teams with some elaborate battery stations but I am looking for an inexpensive way to ensure that our batteries are fully charged before each match.

Recently I bought a Wel-Bilt 125 Amp battery load tester from Northern Tool but not sure how well this will fit the bill.

Anyone with experience with this tester or with helpful suggestions is appreciated.

Thanks and Best wishes to your teams at the competitions...

Re: How does your team charge & test batteries?
 

As a preseason project, we made a batter charging station. it is on wheels and painted our team's colours. It can charge 12 batteries at once and is nicely organized.

Re: How does your team charge & test batteries?
 

We just use the load tester you bought to test batteries preseason. During competition we a Fluke voltmeter to check how charged the battery is. As for a system of charging batteries, we label each battery a letter. Starting with A we use them sequentially for each match. This seems to work for us because the battery we use next is the one that has been charging the longest and theoretically should have the best charge. I hope this helps!

Re: How does your team charge & test batteries?
 

Buy a Battery Beak!!! Such a great product! I sound like an infomercial but after using one of these things I will never need anything else for batteries.

http://www.crosstheroadelectronics.com/Beak.html

Re: How does your team charge & test batteries?
 

We use the battery beak during competition. Full charge is 115% or above. In the off season we perform a capacity check on the batteries to ensure they are still useable.

We also built a 9-battery charging station using the tripple battery chargers from Andymark. They are much better than the charger FIRST supplies with the KOP.

Re: How does your team charge & test batteries?
 

Our battery charging station uses 2 4-bank battery chargers (http://tinyurl.com/a95lyts) to charge our batteries. It can probably hold 12 batteries, but we only have 8 good ones which is why we bought two 4-bank chargers. The chargers have led lights that are supposed to represent the charging state of each battery, and they seem pretty reliable, but we just use a standard multimeter to test batteries. That Wel-bilt tester seems like it would work fine, but it doesn't seem to do anything that a multimeter couldn't. Anyways hope this helped!

Re: How does your team charge & test batteries?
 

The only thing a multimeter will tell you is voltage. You can charge a battery that is shot to 13V, but it could drop out on you 15s into the match. A multimeter won't catch that.

Re: How does your team charge & test batteries?
 

This. I accidentally put a battery just like this in our robot in 2009, went from 13 to 7 volts after the match started (the battery had been killed by trying to test a motor that was shorted, and happened to find a way into the rotation of good ones).

You can ask Akash, we were allied with 11 in that match. There's nothing worse than losing a match because of an error. :(

Edit: I wish I had a battery beak, it would have prevented the mistake from ever happening. Reason being that the battery beak puts a load on the battery, so if it's actually dead, the beak will show it. Best. Tool. Ever. Wish they existed in '09

Re: How does your team charge & test batteries?
 

Using a multimeter to check the voltage of a battery is only accurate to know the charge status of a battery, not whether it is "healthy" or not. Some batteries may appear to be fine after checking the voltage but will not be able to provide high current draw without significant voltage drops.

Load testers will give a more accurate assessment of the health of a battery.

Re: How does your team charge & test batteries?
 

Japper,
I would recommend against the use of the device you list. It is intended for batteries with a much higher capacity/peak current. Continued use of this device is likely to shorten your battery life.
The use of the West Mountain Radio CBA III or the Battery Beak is a much better choice for FRC batteries. The CBA will allow you to test the battery the same way method as used by the manufacturer and the Battery Beak is a simple, pocket tool to give a good indication of battery health.
As pointed out above, a voltmeter tells you nothing other than a cell is shorted of the battery is open.

Re: How does your team charge & test batteries?
 

The Wel-Bilt 125amp tester doesn't look like it's intended to be used like the CBA (i.e. hooked up to the battery and left for a period of time discharging the battery).

It's more like the Battery Beak, only with a much higher load.

Is a 125 amp load applied to the battery for 5 seconds once or twice a year going to harm the battery?


* @ Japper: can you post a pic of the user instructions for this product? I couldn't find them online.

Re: How does your team charge & test batteries?
 

Do you use it to test Cold cranking amps (CCA) and a start test or do you just connect it to
a battery to measure the voltage under a load?

If you are testing CCA what are you setting the CCA value to?

Not a bad tester for $24 (on sale)...but I had to upgrade mine with a pair of anderson connectors
beween the unit and the clamps...

thanks

Re: How does your team charge & test batteries?
 

I scanned the instruction manual in and attached it to this post...

thanks

Re: How does your team charge & test batteries?
 

Ether,
The sheet is hard to interpret but the specs state CCA of 200-1000 CCA. Each test lasts 5 seconds. If the tester is in the 200 amp setting it might be OK for our batteries but we rarely will draw current for that length of time. My general rule of thumb is always to submit the battery to the least amount of shock. This type of tester will ultimately lead to decreased life in my opinion.

Re: How does your team charge & test batteries?
 

I don't know all the specifics but 955 built a 4 battery cart with a custom board that drains batteries all the way before charging them again to ensure maximum charge. Probably too much to do before competition as it took them 3 years

Re: How does your team charge & test batteries?
 

Al,

The unit draws only 125 amps, not 200. The CCA setting on the tester doesn't change the load on the battery, it just affects the computation that the tester displays.

I would use this tester in combination with an inexpensive digital voltmeter to get a reading with more resolution.

Asking an FRC battery to supply 125 amps for 5 seconds is no different from what these batteries often see in competition.

Re: How does your team charge & test batteries?
 

That is good to know that this tester may not harm the batteries, as I certainly
wouldn't want to put any additional drain on the battery in the process...

I'm not sure but I am under the impression that when this tester is plugged into a 12 v
battery that it is measuring the voltage under a load (unlike a DMM/ Voltmeter might do)
and the
CCA start test is an additional load test that is selected by adjusting the
CCA voltage on the tester before performing the CCA start test.

Is this correct or is the tester only reading the voltage without a load (like a DMM/ Voltmeter
might do) when the CCA start test button is not pressed?

I wanted to do more than just measure the voltage as I experienced the same situation once
where we had a battery that measured 13 V and it died too soon during a competition...
Once is enough for me thanks...

Thanks for the suggestions and feedback!

Re: How does your team charge & test batteries?
 

OK, I just found out that the battery is not under load until you press
the start test button which applies a load based upon the CCA
(cold cranking amps) that is selected to match what the battery is rated
at but what would be a safe value of this to test the batteries against?

Re: How does your team charge & test batteries?
 

Aside from a charging station/battery beak, we cut up red and green pool noodles in 1 inch slices (the kind with the hollow center). When a battery comes off the robot after a match, we pop a red noodle around the wire. When the battery is fully charged (and checked with the beak), we put a green noodle on it. This way, we always have a stock of recognizable and fresh batteries for the quick turnaround matches on Saturday afternoons.

Re: How does your team charge & test batteries?
 

This tester is clearly marketed as a 125 amp tester. I doubt that the selection of the CCA rating affects the load that the tester actually supplies -- only the way the tester interprets the data and displays it on the 3 LEDs. But to be on the safe side, set the CCA to the lowest value anyway (200).

I recommend that you ignore the LED readout, and use the actual voltage under load, and compare it to the value for a known good battery, and keep a time history of each battery's results to see trends.

Re: How does your team charge & test batteries?
 

The battery beak is an awesome product for a quick check, but it absolutely will not identify poorly performing batteries.

For that, I strongly recommend what Al has suggested a number of times. A West Mountain Radio battery tester.

Even this year, we found several batteries that would test fine on the battery beak, run fine at a 1 or 2 amp draw, then suddenly dump down so that their final amp hour rating was 13 or 12 Ah, rather than around 18.

Re: How does your team charge & test batteries?
 

The Wel-built load tester like most inexpensive load testers intended for testing automotive starting batteries just load the battery at 125 or 100 amps so you can measure the voltage and infer the CCA based on the voltage under that load.

They do not put excessive strain on the batteries if occasionally used per their instructions and they are a good way to see how the battery will perform when asked to supply the kids of loads that one might see in a match.

The Battery Beak is good for seeing the internal resistance of the battery, which does give you some insight as too its health, and it's SOC.

A volt meter will only give you and indication of the SOC but no info on the health of the battery.

Re: How does your team charge & test batteries?
 

...which is why I said in my previous post that changing the CCA setting on that tester doesn't change the load, it just changes the way the tester computes and reports the battery's health: Presumably if you've told the tester that the battery under test is 500 CCA it expects to see a somewhat higher voltage under load than for a 200 CCA battery.

Re: How does your team charge & test batteries?
 

You are correct.

Re: How does your team charge & test batteries?
 

Never drain these batteries all the way down. This is a technique that was used on old chemistry NiCad batteries, never for lead acid.
Ether, the instruction sheet is very misleading by specifying 200-1000 amps and then specifying 125 amps. A team once showed me a tester they were using to make tests and when they connected it to the battery a resistor glowed inside. Since that day, I have been leary of any automotive type tester.

Re: How does your team charge & test batteries?
 

I've never seen a load tester intended for automotive starting batteries that loaded the battery except when the momentary switch was activated. When that is done yes you can see a resistor glow in some of them IF you leave in in the "load on" position long enough.

As mentioned above all of this style (inexpensive) load tester I've ever seen applies a fixed load of 100 or 125 amps and is only intended to do so for 5 or 10 seconds. Now there are testers out there that are adjustable and can put a higher load on the battery but I've never seen one that didn't cost hundreds, if not thousands, of dollars.

Really there is no reason to be leery of this style of tester. For it to be able to drain a healthy, fully charged, FRC legal battery down to a 0 SOC you better have some serious gloves on because it will become too hot to touch, or you'd have to run the test over and over and over again w/o charging the battery. The key is using it as intended with no more than a 5 or 10 sec load on the battery.

Re: How does your team charge & test batteries?
 

It's written in Chinglish, Al. Ya gotta read between the lines.

Re: How does your team charge & test batteries?
 

We use a Dual PRO RS3 and it works great. We used to use a raw car battery charge with 9 batteries in parallel but it only charged the battery to 12.6 volts and slowly.

We put a boat battery on are cart with a Turnigy accucell 6 wired up for internal charging, Last minute queue charging and secret overnight charging. What's nice about it is that it has a display to show the voltage and it runs of a 12v supply (it will charge above 12v). It's also dirt cheap

Re: How does your team charge & test batteries?
 

One of our mentors built us a battery tester back around 2009 that puts a 30 amp load on the battery with voltage feedback, leave it on for about ~15 seconds and hope your around 11.5V...

Re: How does your team charge & test batteries?
 

My team has a battery cart with a 3-way charger like this one. We use a Battery Beak for testing. I highly suggest the Battery Beak. Hope this helps.

Re: How does your team charge & test batteries?
 

You do realize that this charger is designed for NiMH and NiCD batteries and is not appropriate for charging lead acid?

Re: How does your team charge & test batteries?
 

And also secret overnight charging is probably not a good idea. Thee is a reason they turn off power to the pits overnight...

We did our evening charging by bringing batteries and chargers back to the hotel. This carries it's own risks, but is safer than burning down your pit.

Re: How does your team charge & test batteries?
 

For some reason its not listed on the webpage but it does have a Pb(lead) mode. It charges to the exact same voltage as are Dual Pro RS3.

Re: How does your team charge & test batteries?
 

We do it in our mobile machine shop.

Re: How does your team charge & test batteries?
 

No matter your level of FIRST, the Battery Beak is a must. It's proven to me which batteries are usable for match play and which are only for home testing.

We use 2 of the triple bank chargers on a cart made of recycled robot and prototype material. The cart also contains a Black & Decker charger with the plug on it for the battery along with 2 drill chargers, kit containing battery tags and the previously mentioned battery beak, and battery spill kit.

Edit: We leave our chargers at the pits at the competition but to cover ourselves we take 2 or 3 batteries back the hotel and put them on chargers. That way if the venue turned off the power, we've got enough to practice with and have 2 match batteries.

Re: How does your team charge & test batteries?
 

YouTube video of a tester similar to the Wel-Bilt 125 provides supporting evidence for the above.

http://www.youtube.com/watch?v=tVHlG9qgr8k

Also, the Schumacher BT-110 manual is written in English and is much more detailed than the Wel-Bilt manual:

http://www.batterychargers.com/Docum...-99-000437.pdf


If you're going to use the Wel-Bilt tester for FRC, I still think this is the optimum way to do it.