Lithium battery for 94 gs500

[smoret1704]

Hello, thinking about changing my old gel battery for a new lithium battery and have a hard time understanding what type of battery to get.
My bike is using a 12v 14ah battery now and was looking online for a litium with the same amp but all i can find is much lower, all was under 10 ah, does this matter or do i need to have the same ah?

Will a 12v 5ah lithium work or will that drain to quick and not recharge or is that fine?

[gregjet]

You need to figure whether Li poly or LiFePO4 type battery. The latter is probly a lot better.
I have LiFePO4's in all my bikes. You seem to need a WAY bigger capacity ( it have reservations about the way they measure them). Most of mine have been Shorai's. They originally recommended the same capacity but the CCA of these was lower than required. They finally changed their recommendations but not sure they updated everything.
BTW LiFePO4's will charge with an ordinary leadacid charger and you don't have to be kid gloves with most as they have their own internal charge regulators.
Recommended is 11AHr. for LiFePO4 I would go atleast 14 and at least 192CCA.
The difference if weight is incredible and Li batteries don't care about physical orientation at all. You can mount them upside down if you want so you can consider other places to put them if you have the desire.

[mr72]

A 12V 5ah LiFePO4 will work to start the bike if you only ride when it's warm (>60F) and you don't mind having to be extra attentive to giving the battery warm-up time (turn on the headlight for like 1-2 minutes before attempting to start). And it'll only start the bike about two or three times before you ride it long enough to charge.

I wrote extensively about my experience with this and IMHO unless your charging system is in MINT condition you will be unhappy with the performance of the LiFePO4 battery even if you get a 11-12aH battery. And a 180+CCA 11aH LiFePO4 may be lighter than the stock battery but it's not much smaller if any and it's a LOT more expensive than an AGM.

You can read my other experiences here: http://gstwins.com/gsboard/index.php?topic=71055.msg868438#msg868438

IMHO, LiFePO4 is not the right choice for a Mk1 GS500. If you do what gregjet suggests and get a 12aH LiFePO4 then it will probably work ok but you still have the problem of charging voltage and potentially having to warm the battery prior to starting. It'll cost at least 3-4x as much as an AGM battery. I got a 12aH 190CCA AGM battery for like $45 and an equivalent LiFePO4 would have been like $230+.

[twocool]

Motobatt...AGM....works great..no problems whatsoever....fits nice...multi terminals....no need for vent tube. blah, blah, blah.

Best of all, it is YELLOW, so it has to be good.

Fancy Li battery, nah...Spend your hard earned cash on something else.  If you're worried about the effect of that tiny weight difference...take a good crap before riding ...


Cookie

A 12V 5ah LiFePO4 will work to start the bike if you only ride when it's warm (>60F) and you don't mind having to be extra attentive to giving the battery warm-up time (turn on the headlight for like 1-2 minutes before attempting to start). And it'll only start the bike about two or three times before you ride it long enough to charge.

I wrote extensively about my experience with this and IMHO unless your charging system is in MINT condition you will be unhappy with the performance of the LiFePO4 battery even if you get a 11-12aH battery. And a 180+CCA 11aH LiFePO4 may be lighter than the stock battery but it's not much smaller if any and it's a LOT more expensive than an AGM.

You can read my other experiences here: http://gstwins.com/gsboard/index.php?topic=71055.msg868438#msg868438

IMHO, LiFePO4 is not the right choice for a Mk1 GS500. If you do what gregjet suggests and get a 12aH LiFePO4 then it will probably work ok but you still have the problem of charging voltage and potentially having to warm the battery prior to starting. It'll cost at least 3-4x as much as an AGM battery. I got a 12aH 190CCA AGM battery for like $45 and an equivalent LiFePO4 would have been like $230+.

[smoret1704]

Well its not so much about the weight im worried about, im going to rebuild the seat so space might be a bit of a problem. So a small battery will give me more space for storage and other stuff. Dont thing a full size battery will fit under the new seat.

Motobatt...AGM....works great..no problems whatsoever....fits nice...multi terminals....no need for vent tube. blah, blah, blah.

Best of all, it is YELLOW, so it has to be good.

Fancy Li battery, nah...Spend your hard earned cash on something else.  If you're worried about the effect of that tiny weight difference...take a good crap before riding ...


Cookie

[mr72]

Well its not so much about the weight im worried about, im going to rebuild the seat so space might be a bit of a problem. So a small battery will give me more space for storage and other stuff. Dont thing a full size battery will fit under the new seat.

You're not going to get much more space with a LiFePO4 if you get one that's big enough to reliably start the bike, even when it's warm.

[Joolstacho]

Bear in mind that Lithium batteries are much more sensitive to charge / discharge conditions. They don't tolerate over-discharging. They require specialised voltage control electronics. Lead acid batteries including GM tech are much more robust and suited to a bike's comparatively simplistic voltage control. I don't want to be alarmist but check YouTube for potential explosion too.
I'd be interested to hear other points of view of Li** cells that are being sold for motorcycle use, - my experience is based on years of Lipo use in other applications.
I personally wouldn't dream of using them on an 'everyday' bike, - maybe race bikes which can have the lipos charged by specialised lipo charger in the pits, not by the bike's charging system.

[Watcher]

Well its not so much about the weight im worried about, im going to rebuild the seat so space might be a bit of a problem. So a small battery will give me more space for storage and other stuff. Dont thing a full size battery will fit under the new seat.

You're not going to get much more space with a LiFePO4 if you get one that's big enough to reliably start the bike, even when it's warm.

It'll still be considerably smaller.  I'd say "Around half the size" is colloquially accurate.  They're like, what, 30-40% smaller than AGM?

[Endopotential]

I had to go with a Lithium battery because of my cafe racer seat build as well.

Antigravity Small Case 8-Cell Lithium Ion Battery AG-801, 240 CCA and 9amp hours. 

Pricey, but crazy light.  I've never had trouble with it turning over the bike, and seldom even need a trickle charger with riding the bike only a couple times a month.

[gregjet]

mr72 has a point about temperature. I live in the tropics so it is never a problem, but have seen that they are a bit finiky in colder climates. I have read that the trick is to have the lights on for a minute or so which warms the battery internally.
I did ride my Tr650 down to Phillip Island and I was down to 1degC on a couple of days and I had no problems, but that was only short term.
I know LiPoly batteries have overdischarge problems, but I personally haven't had them with LiFePO4 batteries. LiFePO4 also hold charge for much longer than a Lead acid.
ShoraI tend to "pad out" the cells so the battery case is only a bit smaller that the battery they replace. Some of the other brands seem to do the same. The difference in weight is amazing though.
There is a lot of resistance to them for some good reasons , though those reasons will become less true as the tech develops and Lithium Iron Phosphate batteries are the subject of enormous development at present. I suspect they will completely replace lead/acids soon as OEM when a few more issues are ironed out...that is unless that develop something better.

[mr72]

mr72 has a point about temperature. I live in the tropics so it is never a problem, but have seen that they are a bit finiky in colder climates. I have read that the trick is to have the lights on for a minute or so which warms the battery internally.

Yes, that's supposed to be the trick. I had a way-undersized LiFePO4 battery and along with LED lighting the run-lights-for-a-minute trick didn't work. It worked OK if it was above about 70 deg F, it was iffy at 60-70, and would not start at all below 60F.

Worse yet, what happens when you try to run the starter with insufficient current capacity is that the starter doesn't turn but it still draws current, as much as possible, from the battery, so it heats. I think this may be partially to blame for my starter going belly-up. If the rotor sits still and the commutators draw current and heat up locally they oxidize pretty rapidly. Anyway, I repaired the starter so it wasn't that big of a deal but I do kind of blame my batt.

FWIW my batt was (IIRC) something like 110 or 120 CCA. The starter on the GS draws something like 60-80A during normal operation. This should have been enough. My old Scorpion AGM batt went "bad" when it was at half of its rated 180CCA, measured 90CCA and it would intermittently not start the bike.

LiFePO4 battery has to have like 14.4V charging voltage and perfectly balanced cells to charge to 90%, and it takes 14.6V to get to 100%. My GS500 charging system, even with redundant connections and wiring removed to minimize wiring resistance, will only make 14.4V when all of the connections are freshly cleaned. I'm not sure the regulator will allow more than 14.4V anyway. At idle I have measured mine in the 13s, and a LiFePO4 pack won't charge past 20% until the charge voltage exceeds about 13.6V. See here for more detail. This is why you are dancing with the devil if you try to get away with an undersized LiFePO4 battery in a GS500...

If you are only worried about space and not weight you can probably find an AGM that will fit that is 1/3 shallower than the stock batt and something like 140 or 150CCA. It will be more reliable and far cheaper. It will clear a little space on top of the batt in the stock battery tray. You will need to do something about the end terminals since on a stock GS they come in at the wrong angle and you may have a real hard time getting them to fit at a right angle without the positive terminal coming real close to the frame or battery tray, too close for comfort. Mods to the battery tray and some significant reworking of the wiring is in order. That's what endoptential did ... and endo, you're riding in CA, right? Bay area if I recall correctly? Temp issues should be minimal. It's almost always 60F+ around there.

I agree LiFePO4 batteries will become the standard for motorcycles in a few years, maybe a decade. But they will remain difficult to retrofit into an old motorcycle that was designed to work with lead-acid wet cell batteries that happily charge at 13.2V and above.

[gregjet]

It just hit me about the charge voltage.
They seem to work well in my bikes ( so long as I put them in overrated). But as you say the charge voltage SHOULD be over 14.8v ( 4x 3.7v of a single cell). There must be a step up circuit ( switchmode?) in the case to do it reliably. Didn't even think of it before. I AM getting old...

[mr72]

Maybe the Mk2 GS500s have a different reg/rect with more voltage... or maybe there's a variability to them. Either way you really need 14.6V+ to reliably charge a LiFePO4 so it's worth checking the voltage at the terminals on your bike before ordering the Li batt.