Which LVA

whiteturbo

Pedelecer
Jul 22, 2016
134
25
75
Bristol UK
I use Hobby-King Multistar Li-Po Batteries because they are cheaper and i am used to Li-po's because of my other hobbies so they don't worry me. But as there are no BMS involved it does mean you have to be careful, i only balance charge and i have set full charge to 4.16v a cell on my icharger and i don't go below 36 volts discharge(3.6v a cell). In the interest of improved safety i'm thinking of getting some Low voltage Alarms(LVA) in case i develop a bad cell or get a short and wonder which LVA other guys are using. Are there good and bad ones and how accurate are they, or am i getting paranoid in my old age and should i continue just with careful monitoring.
 

KirstinS

Esteemed Pedelecer
Apr 5, 2011
3,224
899
Brighton
I use Hobby-King Multistar Li-Po Batteries because they are cheaper and i am used to Li-po's because of my other hobbies so they don't worry me. But as there are no BMS involved it does mean you have to be careful, i only balance charge and i have set full charge to 4.16v a cell on my icharger and i don't go below 36 volts discharge(3.6v a cell). In the interest of improved safety i'm thinking of getting some Low voltage Alarms(LVA) in case i develop a bad cell or get a short and wonder which LVA other guys are using. Are there good and bad ones and how accurate are they, or am i getting paranoid in my old age and should i continue just with careful monitoring.
I use , or rather used them, on my bikes until I got a good feel for when they are low. Combo of how the bike was handling , speed drop and handbar readout seems to be as accurate after got the feel embeded

I did find their accuracy to be but questionable. Good enough but nothing like as accurate as my multimeter
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
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5,785
The European Union
I use the LCD voltage readout most of the time because alarms aren't loud enough in traffic. I have a 4S Multistar brick which, while not dangerously unbalanced, isn't as good as i could be. It always gets an alarm. The top ones are good to the 0.01v and set to buzz at 3.65v:

bfbattery.JPG
 

Powerbikes

Trade Member
Sep 11, 2017
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31
39
Whitehaven
www.powerbikes.uk
Exactly the same ones I use on my 250 quad those at the bottom. Cheap as chips and I thought they were loud. Should be enough as a warning in most riding conditions surely?
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
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Inside a box which is inside a pannier and in heavy traffic not quite loud enough.
 

KirstinS

Esteemed Pedelecer
Apr 5, 2011
3,224
899
Brighton
Exactly the same ones I use on my 250 quad those at the bottom. Cheap as chips and I thought they were loud. Should be enough as a warning in most riding conditions surely?
Me too , but in a soft frame triangle bag. I find so loud it scare the crap out me each time !
 

whiteturbo

Pedelecer
Jul 22, 2016
134
25
75
Bristol UK
Well i am going to give them a try on my new 10,000 mah Multistars, another layer of safety can't hurt, but in my experience the first sign of things going wrong are cells that are not balancing and puffing, although i have had both happen and they didn't blow up, they just got inefficient and couldn't do their job anymore so got replaced.
 

danielrlee

Esteemed Pedelecer
May 27, 2012
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Westbury, Wiltshire
torquetech.co.uk
There is an argument that these LVA's can make things less safe. If you forget to disconnect them, they will drain the first cell in your pack (they are powered by only a single cell), possibly causing irreversible damage.
 

whiteturbo

Pedelecer
Jul 22, 2016
134
25
75
Bristol UK
There is an argument that these LVA's can make things less safe. If you forget to disconnect them, they will drain the first cell in your pack (they are powered by only a single cell), possibly causing irreversible damage.
That is something i hadn't considered but i am sure i can fit it into my routine and generate the habit of disconnecting batteries AND LVA's when i first get home from a drive.