Battery Time, here we go!

    I have a 2017 which I bought at the end of year. It has the motorcycle type battery. I intended to replace the battery in caution about this time. It's been running strong & I have it on a tender now (cold up north). I have a jump box suitable for an 8 cylinder engine start tucked in the storage area. Decided I'm going to push the limits and stay with the battery for one more year.

    I have been using the Green battery tender on my Harley battery for the last two years. Leaving the tender on full time. I have now killed two AGM batteries in the two years with two (different) battery tenders because I thought something was wrong with the first battery tender. The tenders say that they are good for AGM batteries even on the web site. But now I am not believing it. Has anyone else had this problem. The reason I am asking now is Sling II has the small AGM battery and I am only driving it every two or three weeks and I WILL NOT leave the battery tender on it because of this problem. I just top it off every couple of weeks and then unplug the tender.

    Quote from Bigdog

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    how much power does a motorcycle battery lose every week

    Well, batteries store energy, not power, so the answer is none, i suppose.

    A relatively new battery, properly installed, clean terminals, etc. and well maintained loses very little. The chemical components of a battery can and do deteriorate over time. Modern batteries are sealed to prevent oxidation, a major source of deterioration. The quality of materials and the quality of the manufacturer's process counts, too.


    The rate of energy loss over time changes. But the main problem is that as batteries get older, the deteriorated internals cannot store as much energy. They fail more quickly because they are closer to the critical point when fully charged than a new battery is.


    Sorry, the answer to your question just isn't as simple as knowing a number.

    The smarter you get, the funnier I am.

    Quote from FunCycle

    I have been using the Green battery tender on my Harley battery for the last two years. Leaving the tender on full time. I have now killed two AGM batteries in the two years with two (different) battery tenders because I thought something was wrong with the first battery tender. The tenders say that they are good for AGM batteries even on the web site. But now I am not believing it. Has anyone else had this problem. The reason I am asking now is Sling II has the small AGM battery and I am only driving it every two or three weeks and I WILL NOT leave the battery tender on it because of this problem. I just top it off every couple of weeks and then unplug the tender.

    I bought the specific tender recommended in the 2019 SS owners guide, (BatteryMINDer Model 2012-AGM). So far, no issues, but I've only had it on the tender a couple of times. Now that winter is here it will be on the tender most of the time.

    Quote from Frankie55

    I have a 2017 which I bought at the end of year. It has the motorcycle type battery. I intended to replace the battery in caution about this time. It's been running strong & I have it on a tender now (cold up north). I have a jump box suitable for an 8 cylinder engine start tucked in the storage area. Decided I'm going to push the limits and stay with the battery for one more year.

    I've thought about buying one of those (jump box) for the sling. How well do they hold a charge? I assume you have to top them off occasionally? Do you have jump posts installed on your sling somewhere?

    I am in the process of converting my motorcycle battery to a car battery now. I have many years of experience with motorcycle and quad batteries and they simply fail too often and without warning (Dammit! It worked yesterday!). I don't have much for electrical mods so that was not part of my decision. I expect to get 3-7 years out of a car battery and 1-2 from a motorcycle battery.


    I don't think I've ever replaced a functioning battery. I have a 'party 'till you puke' mentality. That being said, when my truck batteries went bad a couple months ago (2013 and 2014 batteries), the starter slowed down and told me I had a problem, and I replaced them before being stranded. You will not see this with a motorcycle battery - they just quit.

    Remember folks - this isn't a rehearsal, this is The Show!8)

    Quote from SZurlo

    I've thought about buying one of those (jump box) for the sling. How well do they hold a charge? I assume you have to top them off occasionally? Do you have jump posts installed on your sling somewhere?

    I bought a small jump box on amazon and I’m impressed with how long it holds a charge even after being used to jump several times.....I did put the jump posts in....

    Quote from SlingLow

    I am in the process of converting my motorcycle battery to a car battery now. I have many years of experience with motorcycle and quad batteries and they simply fail too often and without warning (Dammit! It worked yesterday!). I don't have much for electrical mods so that was not part of my decision. I expect to get 3-7 years out of a car battery and 1-2 from a motorcycle battery.


    I don't think I've ever replaced a functioning battery. I have a 'party 'till you puke' mentality. That being said, when my truck batteries went bad a couple months ago (2013 and 2014 batteries), the starter slowed down and told me I had a problem, and I replaced them before being stranded. You will not see this with a motorcycle battery - they just quit.

    The biggest problem with lead acid batteries is using tap water in the battery's. Use only distilled water. Also you need to check the levels and top off on a regular time frame, even on the so called mainteaince free batteries Even in my lawn mowers with both types of batteries I have normally gotten 3 to 4 years out of them. Motorcycles and the lawn mowers since 1971. Even in the 1998 Pontiac TA which has not be cranked in about 8 weeks (lead acid). The only time that I have had a problem is the last 2 years with the AGM battery in/on the Harley of which has normally had the Battery Tender plugged in full time. As I stated in post # 2

    Quote from FunCycle

    The biggest problem with lead acid batteries is using tap water in the battery's. Use only distilled water. Also you need to check the levels and top off on a regular time frame, even on the so called mainteaince free batteries

    I always use distilled water and service at least once a year but what about checking maintenance free batteries? I didn't think they could even be opened but I haven't tried or closely examined one. I figured maintenance free meant maintenance free. Flooded/maintenance free is what I got for the Sling in a group 26 (deka battery for $85).

    Remember folks - this isn't a rehearsal, this is The Show!8)

    Edited once, last by SlingLow ().

    Quote from SZurlo

    I've thought about buying one of those (jump box) for the sling. How well do they hold a charge? I assume you have to top them off occasionally? Do you have jump posts installed on your sling somewhere?

    I bought one of these for every vehicle we own and gave one to every one of my kids (and future daughter in law). Already saved her once when she got off work late and her car wouldn't start in a very deserted parking lot. They hold a charge for a long time and don't take up much space (they make some really small ones that are capable of jumping up to V8 engines). Jumper cables take up a lot more space and require someone to be around that can jump you.

    FB - North Alabama Polaris Slingshot Owners - (Huntsville)

    Quote from SlingLow

    I always use distilled water and service at least once a year but what about checking maintenance free batteries? I didn't think they could even be opened but I haven't tried or closely examined one. I figured maintenance free meant maintenance free. Flooded/maintenance free is what I got for the Sling in a group 26 (deka battery for $85).

    You can pop the top off of the cells on the maintenance free batteries, most of the time the cap includes 3 cells. Top the cells off with distilled water. I have done this every since they were put on the market to the buying public.

    picked up my 2015 SL December 20th 2014 still using the same battery going strong. I just keep it on a trickle charger over the winter here in Maine. But since it's five years old my experience with batteries is they usually go bad around the 7-year Mark. So I will be replacing it in the next year or so.

    Quote from SZurlo

    I've thought about buying one of those (jump box) for the sling. How well do they hold a charge? I assume you have to top them off occasionally? Do you have jump posts installed on your sling somewhere?

    The jump box I have holds a charge incredibly long! I just checked it after 4 months still at 95%. I recharged it again and it should be good to go for most if not all winter. I have never used it and can't remember the numbers but I have an F150 so I made sure it was rated for an 8 cylinder auto. Some are better suited for smaller engines so it may make a difference.


    I do not have jump posts installed but I have a ratchet and apex to remove the battery cover. The terminals on the smaller battery's are exposed so it shouldn't be an issue.