View Full Version : Rattling Battery?
sanddrag
22-12-2015, 22:39
Has anyone ever had a battery rattle inside? I have a Genesis battery that sounds like it has plastic pellets inside when you shake it, like a musical maraca. What causes this?
We use several pallets of the Genesis batteries per week in the UPS' we build at work. I have never heard of such a failure mode. The only think I can think of is if the battery was dropped and part of the internal structure that holds the lead plates in place has broken, allowing the lead plates or the broken bits of plastic to rattle around inside.
protoserge
23-12-2015, 01:24
I'd mark it damaged and recycle it.
Are you absolutely sure the screws/standoffs on the terminals aren't loose?
sanddrag
23-12-2015, 01:25
Are you absolutely sure the screws/standoffs on the terminals aren't loose?Affirmative.
Anything that stores energy has the potential of dangerous failure modes. I would call it broken and recycle it. At the very least I would only use it in a static application and not on a moving robot.
If the screws or standoffs on the terminals are not loose, then the rattling is internal. Without knowing the internals details of the battery housing, I would do as several of the other people in this thread suggest, send it to recycling. If it is really just an "unimportant" bit of plastic rattling around, you might not have a problem. If that bit of plastic was holding the lead plates in place, the plates might end up shorting out at some point, maybe much later. Such a short can cause the battery to explode and spray acid everywhere. It is just not worth the risk, even if you are on a "low resource" team.
protoserge
23-12-2015, 21:07
It is just not worth the risk, even if you are on a "low resource" team.
The newer rules make batteries much more affordable (~$25-35 shipped for some) so I would find it hard to use the "limited resource team" line.
sanddrag
23-12-2015, 21:40
The newer rules make batteries much more affordable (~$25-35 shipped for some) so I would find it hard to use the "limited resource team" line.While we're on the topic, what is your source for these $25-$35 shipped batteries? Also, given all the various choices in batteries now, is there a clear "best" battery in terms of performance?
GreyingJay
23-12-2015, 22:30
Do we know for sure that the battery equivalency rule introduced in 2015 is here to stay for 2016?
protoserge
23-12-2015, 22:45
While we're on the topic, what is your source for these $25-$35 shipped batteries? Also, given all the various choices in batteries now, is there a clear "best" battery in terms of performance?
Check out Battery Sharks for the Sigmastek (sp?). 1 battery (http://www.batterysharks.com/12-Volt-18-Amp-SLA-Battrery-Free-Shipping-p/12v-18ah-f_b12-18.htm) 2-pack (http://www.batterysharks.com/Set-of-Two-12V-18AH-Batteries-Free-Shipping-p/12v-18ah-f_b12-18_x2.htm). If you exercise the single battery without shipping option (https://www.batterysharks.com/ProductDetails.asp?ProductCode=12V-18AH_B12-18&CartID=1), you can get 4 for $115ish shipped (at least to my zip code).
I don't expect a rule change on this, but buying cheaper 12V batteries should be on all teams' radar for practice and non-competition use. Proper battery management will get at least 4 seasons of use.
There is no real difference between the batteries in capacity or construction. When I was on 836, we ran several brands (MK, Genesys, National, Sigma/Battery Sharks) and they were pretty much identical in all regards using an accepted test procedure for batteries. adciv can probably provide more detail if you require it.
We've been buying batteries direct from MK Battery for $37.50 shipped.
protoserge
23-12-2015, 23:11
We've been buying batteries direct from MK Battery for $37.50 shipped.
Good to know. Are you using a commercial customer account or just telling them you are a FIRST team?
Good to know. Are you using a commercial customer account or just telling them you are a FIRST team?
Just telling them that we're a FIRST team, looks like they already have the discount set up. Batteries shipped from Anaheim, CA on Tuesday and we received them on Thursday. I just called the number on the bottom of the website.
Chief Hedgehog
24-12-2015, 00:39
A bit off the OP -
Many teams have a Battery+Bulbs (https://www.batteriesplus.com/) in their area. See if they are willing to help out - we have been fortunate enough to get a couple of batteries the last number of years for free (no shipping either!).
The newer rules make batteries much more affordable (~$25-35 shipped for some) so I would find it hard to use the "limited resource team" line.
Yes, the cost of batteries is not that high especially when considering the overall budget. My reference to "low resource" teams speaks more to a perception than reality; i.e. it's not worth it for any team to use a battery that might blow up.
While I don't see there being a battery that is clearly better than others.
There are batteries which would be more suited to the abuse and the high current draw that FRC batteries typically face.
Some Battery manufactures supply intended use information with their batteries. I have found two different types of Panasonic Batteries online, both with similar capacity. The difference lies in their intended use. One battery use statement says "UPS, Security, Alarm, Instrument, Test Equipment, Medical Equipment;This model should be used for standby use only". Where as the other battery says "battery suitable for continuous cyclic usage such as golf buggies & mobility aids/motorised scooters."
Now, the difficult thing to consider is which of these fits FRC best. Typically batteries are charged and then not used for periods of time, then when it comes to events they are rapidly discharged and then recharged continuously. Would a battery intended for a UPS or a battery intended for something like a motorised scouter be superior?
Coming back to the actual intended thread topic, the Rattling Battery seems really strange. I would recommend recycling or disposing of it, it's just not worth the risk.
Al Skierkiewicz
28-12-2015, 07:30
Dave,
Generally there is nothing good about loose particles inside the battery. It is possible that someone dropped something on the cover over the pressure relief valves. Small pieces of plastic may have broken off.
It is also very likely, some of the internal plastic between cells has broken loose. If this is an AGM battery, there may not be any immediate danger. I would recycle before something occurs.
The pressure relief seals at the top of each cell I have seen are mostly rubber and would not rattle if they came loose.
Does the rattle appear restricted to the valve cover?
Would a battery intended for a UPS or a battery intended for something like a motorised scouter be superior?
The difference between these two cases is the speed of discharge and the number of deep cycles the battery will run. FRC matches the scooter/golf cart model (motors/high peak output current, hundreds of cycles over a lifetime) much better than security/UPS (more "slow and steady" discharge when used, probably a dozen cycles per lifetime).
And yes, I concur that the rattling battery should be retired and recycled.
sanddrag
28-12-2015, 11:01
The rattling was much deeper inside, closer to the bottom than the top. I took it in for recycling.
Al Skierkiewicz
28-12-2015, 11:29
Allastair,
Many of the UPS devices we have here use the same batteries that we use in FRC. Interestingly, they also have SB50 (not red) connectors on them.
The rattling was much deeper inside, closer to the bottom than the top. I took it in for recycling.
Could the rattling have just been when driving or was this all the time?
My team thought we had a bad battery too... Found out it was the battery edge vibrating on a piece of wood.
sanddrag
15-01-2016, 12:33
Could the rattling have just been when driving or was this all the time?
My team thought we had a bad battery too... Found out it was the battery edge vibrating on a piece of wood.It was definitely internal. We've since purchased new batteries.
That sucks, good to hear you replaced them
kevin.li.rit
16-01-2016, 00:17
Just telling them that we're a FIRST team, looks like they already have the discount set up. Batteries shipped from Anaheim, CA on Tuesday and we received them on Thursday. I just called the number on the bottom of the website.
I've been using a little place called amazon. (http://www.amazon.com/gp/product/B001DL7D1O?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00) for 35ish.
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