please, teach me about batteries

[ghostdancing]

at 54 years old i never owned an electric starter bike, the first one will be my current chonda\zong169FMM project, so i'm now in the market for a battery: must be smaller as possible, light and cheap (aliex sourced)..can you point me to the best option?

[grhanka]

For a battery you only have three real choices:
1. Flooded cell (the cheapest.)
2. AGM (Half again the price, somewhat longer life, much less damaged by deep discharge.)
3. Lithium (Twice the price of AGM, much lighter, longer lived, and tolerates deep discharge.)

My personal choice is AGM. If you go lithium, be sure it has a built-in charging circuit, because your bike is designed to charge flooded or AGM.

[Megadan]

Light as possible is a lithium. They are so light it is almost comical. They make you think they are fake when you pick them up for the first time. As grhanka said, they are more sensitive to charge voltages and don't do well with the wide range of charge voltages a standard motorcycle charging system puts out. Upgrading to a solid state reg/rec, or sometimes removing the sense circuit from a standard reg/rec can solve this issue. Otherwise, as he mentioned, it needs to have a built in charge regulator. The other downside is cost.

Otherwise, I go for AGM in most of my bikes. I have the best luck with them in terms of service life and reliability. The AGM in my VFR is going on 6 years old and still turns it over strongly. I even forgot to plug it in to my trickle charger this winter, it sat 4 months and still turned over.

[ghostdancing]

thankyou guys! how many amps i do need? the bike will have very simple electric: headlight (35W)\taillight, it's more for offroad; i also need it small, but did not found any measurements info on the aliex listing

also: is AGM gel filled?

[ghostdancing]

I saw that honda crf230 uses a 4 amp battery..is this enough then?

[ChillRider]

Usually bikes in the 200-250cc class have a 6-7Ah battery, but you can often find 8Ah or even 9Ah in the same sizes (typically a YB7-L size or smaller, rarely larger). 4Ah sounds a bit on the puny side, TBQH.

Just make sure that the battery you order will fit: your bike may call for specific dimensions or pole shape/orientation or even accomodate for the presence (or less...) of a gas vent nipple, in which case you will need to be rather specific in your shopping.

[XLsior]

How big is the space for the battery box? I found there was not much difference in battery sizes from 4ah to 7ah...after that batteries jumped up in size. AGM gel for safety and less maintenance. Bought the cheapest 7ah YTX7L-BS from Ebay.

AGM (Absorbed Glass Mat)

[ghostdancing]

i'm oriented on this, for room issue

https://www.ebay.it/itm/175165051084...3ABFBM8um85f1f

[XLsior]

5AH should be fine if that's the best practical fit for the space. the 7AH are 50mm taller... after that all the dimensions get larger.

[Megadan]

Most of the factory Hawk-style bikes come with a 6.5ah battery with 80cca (from memory). A 5ah is a tad on the small side, but should still be sufficient for starting duty and a basic electrical system. Most of us tend to go with a 7 series batter, such as the ytz7s which is a 130cca 6ah battery. That is what I run in my bike and it has never been insufficient.

[Magician16]

When I was having problems with my Bashan, I just used kick starter til I determined that the starter relay was running the battery down and had ruined a brand new battery. I wasn't sure if I had fixed the problem, so I bought a cheap battery, less than $30 that would fit. I put in a Chrome Battery YTX5L-BS. It is more than enough and is way smaller and lightweight. I had to add some styrofoam around it for spacing.

[Countrytour]

Check out fortnine's video on batteries.

[grhanka]

AGM is not gel. Real gel batteries are rare and not that great. Low self-discharge is another advantage of AGM over flooded. After three months the AGM might still have enough charge to start. I suspect Lithium is also good for winter storage, but I haven't tested it.

[JFOlivier]

The problem with the AGM, gell and probably lithium cells is in the charging systems. I have no experience with lithium batteries but have worked on charging systems on gell and AGM banks and the max of 14.2 volts is quite important on these batteries as above that voltage causes gassing which to the AGM's will cause loss of electrolyte and in the gells gas caused bubbles or cavities around the plates which will cause loss of battery capacity over time and eventually leading to failure. AllI can see in the motor cycles wiring diagram are the 3 stator coils leading to a rectifier and am not sure if the output voltage is controlled or not, I suspect not and will try to check what that voltage is when next I remove the Lifans seat. This of course will be charging a Lithium Ion battery.

[JerryHawk250]

Originally Posted by JFOlivier

The problem with the AGM, gell and probably lithium cells is in the charging systems. I have no experience with lithium batteries but have worked on charging systems on gell and AGM banks and the max of 14.2 volts is quite important on these batteries as above that voltage causes gassing which to the AGM's will cause loss of electrolyte and in the gells gas caused bubbles or cavities around the plates which will cause loss of battery capacity over time and eventually leading to failure. AllI can see in the motor cycles wiring diagram are the 3 stator coils leading to a rectifier and am not sure if the output voltage is controlled or not, I suspect not and will try to check what that voltage is when next I remove the Lifans seat. This of course will be charging a Lithium Ion battery.

This is all very true. It's always a good idea to check actual output t make sure you are not over charging. If it does over charge then it would be a good time to upgrade to a better rectifier/voltage regulator. Your battery will later much longer.