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Re: revive dead lithium battery?

Posted: Sun Jan 03, 2021 8:28 am
by Firebolter
The Li battery on my 500 just died. This is the second one I have had go tits up in the last 10 years. While I could recover the first one on the TM, I loose faith in them and it was covered by the dealer, so I had him replace it. The new Li he put it, is BAD ASS! Spins that motor like crazy. I carry a jump pack when I am on the 500 but that gets you started and doesn't address the bad battery when they do go belly up out on a ride. Still blows my mind how many bikes are coming now with no kicker back up now. New KTM 300's 2T's are like that!

The Li's are very sensitive to charger types and input voltage/amps and you should not use chargers with auto desulfation modes like an opti charger. I bought a separate trickle/charger for the mine since 3 bikes have them now. I like how Lithium batts hold a charge and most I have had lasted years with zero issues and very little charging except in the winter months just to make sure they were charged. I am replacing it with a different brand this time vice the OEM.

Anti gravity makes a battery that has a "re-start" mode on it. When the voltage drops to a certain level, it will "shunt" the battery requiring you to push a reset button on the battery, saving enough juice for one more start so you supposedly can't take the voltage too far down to hurt/kill the battery.


https://antigravitybatteries.com/restart-technology/


My OEM from the 500
Image

Re: revive dead lithium battery?

Posted: Sun Jan 03, 2021 3:51 pm
by smdub
Cranks faster because the new battery is larger w/ better cells. The OEM Skyrich is only 2Ah. The Antigravity ATZ7 is 3.3Ah. I replaced the one in the 500 before the KAT. Moved the orig to the 150 (whose orig Skyrich had a bad cell.) I took that orig apart and it's mostly empty space. I could probably fit a 4S2P stack of real A123 cells in there which would be 5Ah and a *TON* of cranking current.
Li batts shouldn't need a charger unless you have parasitic draws. They will hold charge over a year w/ no load on them.

Re: revive dead lithium battery?

Posted: Mon Jan 04, 2021 12:38 pm
by Firebolter
smdub wrote:
Sun Jan 03, 2021 3:51 pm
Cranks faster because the new battery is larger w/ better cells.
It's the same physical size but yeah, just more juice and a better battery IRT capacity than the OEM. What gets me, the OEM ones are 27 dollars more than the Featherweight Li's which get good reviews and the new Anti Gravity "re-start"'s are only 115.00 which is the same price as OEM, from Rocky Mountain anyway.

Re: revive dead lithium battery?

Posted: Mon Jan 04, 2021 1:29 pm
by Firebolter
specs on the Anti Gravity re-start battery

Antigravity ATZ7 RE-START Battery
$129.99

The NEW Antigravity ATZ-7-RS is a hi-power lightweight Lithium-Ion battery, built with our groundbreaking RESTART Technology (built-in jump-starting) so you won’t ever get stranded with a dead battery again! Directly replaces the OEM YTZ7S, YTZ5 and others. 90% of off-road bikes use this size as well as some street bikes.

YTZ7S case size: 4.53 x 2.75 x 3.35 inches (LxWxH)
150 Cranking Amps
7 Amp Hours (PbEq)/ 3.3Ah (Actual)
1.3 lbs
Safest Battery Technology using full BMS and Lifepo4 Lithium chemistry

Re: revive dead lithium battery?

Posted: Mon Jan 04, 2021 1:55 pm
by smdub
By larger, I meant larger capacity. Yes, they are both the same physical size.
Here is what the orig looked like opened. Hard to tell in the pic but it's quite a bit of wasted space. They are pouch cells and not cylindrical cells.
KTM is just using the cheapest battery they can get that still works 'well enough'.
20200706_080312_r640.jpg

Re: revive dead lithium battery?

Posted: Thu Jan 07, 2021 8:37 am
by Firebolter
Got the new Featherweight Li battery from Rocky Mtn. Almost exactly the same physical size as the OEM, fit good. Came fully charged, checked it and it was at the 12.9V they said it should be. Put it in and she spins the motor nicely. 85 bucks and the OEM is 112.

OEM (Skyrich). https://www.skyrichbattery.com/product_ ... cts_id=567
Model HJTZ5S-FP
L*W*H (inches) 4.49x2.80x3.39
Weight .9 lbs
CCA 120 amps
$112.00 from Rocky MTN

Aftermarket replacement (Firepower Featherweight). https://firepowerparts.com/product/feat ... ery/50983/
Model 490-2501
L*W*H (inches) 4.4375x2.75x3.375
weight 1.3 lb.
CCA 150 amps
$85.00 from Rocky Mtn

Re: revive dead lithium battery?

Posted: Fri Jan 15, 2021 11:40 am
by Marylander
I discovered that the antigravity resrart batteries don't even require pushing the button if you completely drain the initial voltage. I have one in my 690 enduro r and left the key on last time I got home with it. When I went to turn it on today I just turned the key off and back on and the thing started right up. Now to remember how to set the clock... Also looks like the bike doesn't depend on the battery to maintain the trip meters (which I use to keep track of miles between fill ups).

Re: revive dead lithium battery?

Posted: Thu Jun 03, 2021 6:48 am
by Laoch
Follow up- RMATV has 2 year warranty on their lion batts. I returned it and got a new one :thumbup:
So, now I have an extra. We popped a lead acid battery in, from Walmart, it works for now.