Sophomore Rider
Currently Offline
Posts: 128
Likes: 3
Joined: Jun 1, 2013 5:11:09 GMT -5
|
Post by gingel on Nov 3, 2013 15:43:28 GMT -5
Hello, I have a 125cc scooter (SYM Brand), and i read that people started to use LifePo4 (Lithium iron phosphate) battery instead of the Lead Acid. People use this also on motorcycles. It is basically a type of lithium battery. This type of battery supposed to last longer, and the weight is much lower. Where i live the prices of the scooter Lead Acid batteries are high and quality is not so good, so i thought maybe to try and install the LifePo4 battery. I saw that there are LifePo4 batteries that looks like the lead acid battery. I also read that people use LifePo4 battery packs that are for radio control toys (planes,cars). From what i understand, if i have a 7Ah Lead Acid battery, then a 2.3Ah LifePo4 supposed to be enough for my 125cc scooter. Anyone here tried to use this, or heard about it? |
|
|
|
Post by prodigit on Nov 3, 2013 17:14:27 GMT -5
Yeah, sure, however you still need at least 4 or 5A for your scoot to start it; I don't think it's comparable to a 2,5a at all; other than that a LiFePo4 battery usually lasts 4 years, vs 1 year for a Lead Acid battery.
They're much better, and as long as you aren't living in the hottest place on earth, and your scoot won't short circuit anywhere, they are great replacements of Lead-Acid batteries.
They last longer. I would only buy one if your scoot is relatively new; not to make it outlast the scoot.
|
|
|
|
Post by SylvreKat on Nov 3, 2013 22:20:03 GMT -5
Seriously? Regular batteries only last a year?
Wow. Mine's the original that came with the scoot back in 2007.
At that rate, the LifePo would last me about 20 years. But does it work on a Battery Tender Jr?
>'Kat
|
|
|
|
Post by JerryScript on Nov 3, 2013 22:31:50 GMT -5
I rode an electric bicycle for 6 years before purchasing my scooter a few months ago. I switched to LiFePO4 after the first year having gone through two sets of SLA batteries. There is one major problem with LiFePO4, you have to either have a BMS circuit board on the battery, or use individual cell chargers rather than just relying on a standard charging system.
The 12v LiFePO4 batteries contain 4 cells, and they are EXTREMELY sensitive to overcharging! If you have one cell that gets significantly lower than the others, one of two things happens: 1- The battery never reaches a full charge, 2- one or more of the "healthy" cells gets overcharged. I could go into a long drawn out explanation of why it happens, but it would be easier to read some ebike forums for details.
If you do decide to try LiFePO4, get at least one individual cell charger, and top off the cells individually weekly. The other option is to get a battery with a BMS (or purchase one seperately), which will use resistors and heat sinks to blead off excess voltage on the cells already charged fully, while waiting for the weaker cells to catch up. A good one will also vary the voltage applied in order to properly fully charge each cell.
LiFePO4 + a decent BMS is not cheap, I personally would recommend sticking with SLAs until the LiFePO4 technology improves and costs come down.
|
|
|
|
Post by alleyoop on Nov 3, 2013 22:42:53 GMT -5
You also need a special charger which checks each cell and tries to charge each cell evenly. I know I fly RC airplanes and I have a couple that I converted from 4 stroke motors to Electric. So the first problem you will have is with the charging system on your scoot it is not designed to charge those kinds of batteries. They also can start on fire and they create a very high temp fire.
Alleyoop
|
|
Sophomore Rider
Currently Offline
Posts: 128
Likes: 3
Joined: Jun 1, 2013 5:11:09 GMT -5
|
Post by gingel on Nov 4, 2013 1:27:48 GMT -5
|
|
|
|
Post by JerryScript on Nov 4, 2013 6:43:15 GMT -5
Those options are viable, but expensive. It also adds complexity, with the possibility of any of the components failing. A tried and true SLA is $30, and no extra circuits that may fail are required. You also need a special charger which checks each cell and tries to charge each cell evenly. I know I fly RC airplanes and I have a couple that I converted from 4 stroke motors to Electric. So the first problem you will have is with the charging system on your scoot it is not designed to charge those kinds of batteries. They also can start on fire and they create a very high temp fire. Alleyoop I fly ornithopters, all with lipos. Getting close to 15 minute flight times with the most recent cells I found online. My Avitron actually gets chased by birds! |
|
Sophomore Rider
Currently Offline
Posts: 128
Likes: 3
Joined: Jun 1, 2013 5:11:09 GMT -5
|
Post by gingel on Nov 4, 2013 8:52:39 GMT -5
Those options are viable, but expensive. It also adds complexity, with the possibility of any of the components failing. A tried and true SLA is $30, and no extra circuits that may fail are required. This is what i mentioned before, where i live (Israel) the prices of scooter maintenance free Lead Acid battery are high. Around 100$ US for a 7Ah battery, and they last maybe 2 years. |
|
|
|
Post by prodigit on Nov 4, 2013 13:05:15 GMT -5
I think most 12V batteries sold online have a BMS installed within them.
A BMS protects from overcharging, and makes sure the battery gets charged optimally.
It's necessary, because a car's stator does not have a BMS system, and the battery will be charged via the 2 poles, so BMS must be on board.
As far as batteries, my battery of my TaoTao ATM50 actually lasted 1,5 years. It still works, but if it doesn't start from the first start, it fails to start any subsequent starts.
I've even had LiPo4 (non-iron) fail after 1 year (they still had 75% left after the first year, and less than 50% of charge left after 1,5 years).
|
|
|
|
Post by JerryScript on Nov 4, 2013 14:40:47 GMT -5
Those options are viable, but expensive. It also adds complexity, with the possibility of any of the components failing. A tried and true SLA is $30, and no extra circuits that may fail are required. This is what i mentioned before, where i live (Israel) the prices of scooter maintenance free Lead Acid battery are high. Around 100$ US for a 7Ah battery, and they last maybe 2 years. That is crazy expensive! If you find it more affordable, go with the LiFePO4, just be sure you have a BMS and individual cell charger, and be prepared to take care of it. Unlike SLAs, these do require careful monitoring if you want to get your money worth of use out of them. |
|
|
|
Post by earlylight160 on Nov 4, 2013 15:37:02 GMT -5
 but I think I'll pass on the LifePo4 until the technology improves and cost drops. I'll stick with my proven system of a good Yuasa AGM and keep it plugged in to my Battery Tender Junior.when not riding.
|
|
|
|
Post by prodigit on Nov 4, 2013 18:46:41 GMT -5
Chances are that LiFePo4 batteries will increase, not drop in cost, as the prices of Li are currently skyrocketing (due to demand from all kinds of sectors, ranging from cellphones, tablets, wrist watches, to larger applications like electric scooters, cars and golf carts).
|
|
|
|
Post by spandi on Nov 4, 2013 19:31:52 GMT -5
|
|
|
|
Post by spandi on Nov 4, 2013 19:40:44 GMT -5
|
|
|
|
Post by alleyoop on Nov 4, 2013 19:44:27 GMT -5
And how does the scoot R/R charge it? Like I said those types of batteries require a special charger. Alleyoop |
|
..BAD TO THE BONE..
