Any Fresh High Quality SLAs Out There?

[doubledipsoon]

I just installed a couple 12 v 15 AH SLAs into my Synergy battery pack and my e-bike could barely get 8 miles out of them. My low voltage cut-out switch even activated on mile 8. This Ebay stuff is amazingly low quality- Anybody out there in SLA BatteryLand know of an outfit that sells ultra-fresh SLA batteries? Hey, I'm even willing to pay more. Or is SLA battery purchasing just another dice throw in a universe of e-bike lies and deception. (You know there's plenty). Any markings on SLAs showing when they were actually manufactured? Disappointed Joe

 

[ian.mich]

Distance seems abour right for 24V 15Ah SLA, there's only a useable 7.5Ah so that's a mere 180Wh. At 8 miles, that makes 22.5Wh/mi.

 

[StudEbiker]

Best to save up if money is a concern and get a lithium battery. :wink:

Lead is dead.

 

[doubledipsoon]

I can always count on responses that never answer the question. First of all, my experience with all prior 12 volt/15 AH batteries, connected to make 24 volts ALWAYS produces 12-14 miles with my Synergy 370 BMC finned motor e-bike. So, 8 miles is way below prior comparisons. (By the way. 370 watts/24 volts= 15.4 amps/hr & going 20 mph for 1 hr is 20 miles, a bit above my actual distance)...As far as lithium ions go, yes, perhaps I should upgrade to one, but that's not my question here on the forum......Hey, thanks anyway for your attempts at followups....Keep hanging in there and try to stay FOCUSED on the topic. Brutally honest in a severely distracted world, Joe

 

[ian.mich]

I can always count on responses that never answer the question. First of all, my experience with all prior 12 volt/15 AH batteries, connected to make 24 volts ALWAYS produces 12-14 miles with my Synergy 370 BMC finned motor e-bike. So, 8 miles is way below prior comparisons. (By the way. 370 watts/24 volts= 15.4 amps/hr & going 20 mph for 1 hr is 20 miles, a bit above my actual distance)...As far as lithium ions go, yes, perhaps I should upgrade to one, but that's not my question here on the forum......Hey, thanks anyway for your attempts at followups....Keep hanging in there and try to stay FOCUSED on the topic. Brutally honest in a severely distracted world, Joe

The peukert effect causes EV SLA batteries to deliver 50% capacity so you'll only get ~7.5Ah from a 15Ah SLA before LVC. I don't think you;ll find very many people to answer your question, i could put together a fully loaded 29.6V 10Ah lipo battery for under $200 incl bulk charger and all wires, plus it would last ~500 cycles, weigh 2kg, charge in 1 hour, and have slightly more useable Watthours. At a mere 7.5Ah discharge (lithium can go to 80 or 90 percent) that is 222Wh vs 180Wh plus all the other benefits.

 

[doubledipsoon]

Ian, How many amps does your LiFePO4 battery support, you know the "continuous amperage output"? You know, one thing I do realize about the Lithium Universe is that hardly any of them can support the motors I prefer- the MAC 600 watt or the old BMC 600 watt, or even the old BMC 400 watters(actually 370 watts). This is the Achilles heel of LiFePO4s- most can only do 25 or 40 continuous output amps, probably even including yours. There is an outfit called ElectricRider out of Austin that makes high amperage output LiFePO4s but they run $500 with shipping and can deliver 95 amps @24 volts- now, that's the other half of the story, Joe PS- How on Earth have I been doing three 14 mile round trips per week on each pair of 14-15 AH SLA's for 8 months before they peter out? 96 cycles worth....

 

[ian.mich]

Ian, How many amps does your LiFePO4 battery support, you know the "continuous amperage output"? You know, one thing I do realize about the Lithium Universe is that hardly any of them can support the motors I prefer- the MAC 600 watt or the old BMC 600 watt, or even the old BMC 400 watters(actually 370 watts). This is the Achilles heel of LiFePO4s- most can only do 25 or 40 continuous output amps, probably even including yours. There is an outfit called ElectricRider out of Austin that makes high amperage output LiFePO4s but they run $500 with shipping and can deliver 95 amps @24 volts- now, that's the other half of the story, Joe PS- How on Earth have I been doing three 14 mile round trips per week on each pair of 14-15 AH SLA's for 8 months before they peter out? 96 cycles worth....

20C discharge Turnigy RC LiCo cells, 20xAh yields the dicharge Amps. So 200A. My battery is 88V 15Ah so it can do 300A, but I use 60A. It's likely your batteries are amiss. I think it is possible to do what you described at the prescribed Wh, under good conditions.

 

[scoot]

B&B brand in the HR seies have a solid reputation for the high discharge usage we aspire to. As to finding "fresh" ones, I think that is probably a constantly moving target, although some vendors are probably more reliable than others... can't tell you which ones since I haven't shopped/researched them in quite some time. I am much happier with my Life packs anyways... parallel a couple of decent Life packs (e.g., Headway P cells) and you can get more discharge capabilty and range at half the weight. And then there there are the A123 packs that give oodles of C. :wink: ... oops off track again... suggest you research the B&B SLAs 8)

 

[dogman dan]

Are you sure your new sla's are EV rated type? If they seem lighter than the others, they aren't. Thin lead will peukerts like mad at 40 amps.

B&B's in the right type will cost ya, but they will be as good as they get.

Get the next batch from a reputable dealer. Like somebody that sells primarily to the wheelchair and mobility scooter market. The ebay guy will be who buys the old stale stock from the wheelchair dealer, or sell stuff never intended for an EV. I'd also avoid a dealer that sells everything, like batteryspace. Go to somebody who sells only to fussy people, like rich old farts with scooters.

I won't argue you into lithium, It's not working on you.

 

[Ypedal]

I put this together recently.. might find interesting

http://www.ypedal.com/sla/sla.htm


like others have said, best bet for fresh, and optimal SLA is a local battery house, interstate dealer , etc.. these guys go thru them fast and tend to keep fresh stock.. buying lead on ebay can be a crapshoot.

if you were getting 14 mile range from your 20ah sla's ..

10ah x 24v = 240wh / 14 miles = 17wh/mile

24v x 20ah = 480wh potential so .. yes.. your 20ah sla are deliverying 10ah at the 1 hr rate.

a proper 24v 20ah lithium pack will double your range.

better yet, going the same 14 miles, on a 20ah lithium pack = 50% discharge capacity = longer life from your pack so they should last 2 to 4 years in stead of just 96 cycles.