Go Back  Bike Forums > Bike Forums > Electronics, Lighting, & Gadgets
Reload this Page >

Please explain battery ratings (lights)

Notices
Electronics, Lighting, & Gadgets HRM, GPS, MP3, HID. Whether it's got an acronym or not, here's where you'll find discussions on all sorts of tools, toys and gadgets.

Please explain battery ratings (lights)

Old 09-29-17, 06:23 PM
  #1  
Falchoon
Senior Member
Thread Starter
 
Falchoon's Avatar
 
Join Date: Oct 2002
Location: Oz
Posts: 979
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 26 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Please explain battery ratings (lights)

So if one light battery is rated at 650 mAh and another at 600 mAh (both being Li-Ion rechargeable) then the one with the highest number is better?

The 600 mAh one is rated at 120 LM and the 600 mAh one is rated at only 90 LM. I know the more Lumens the better for (rear) light output.

The 650 mAh light has only 4 LEDs and the other has 16 LEDs.

The 90 LM/650 mAh one has an advertised run time of 4-8 hours (Hi > Lo > Flash) but the other one doesn't have a run time listed but has diffferent modes (Hi > Mid > Flash > Strobe). Charge time is claimed 3 hours for the 650 mAh one and 2 hours for the 600 mAh version.

Will I (or more importantly, motorists) notice a difference between 90 LM and 120 LM?

Are these claimed ratings accurate? Lights are cheap Asian ones so I'm thinking maybe not...
Falchoon is offline  
Old 09-30-17, 12:49 PM
  #2  
VegasTriker
Senior Member
 
Join Date: Feb 2006
Location: Sin City, Nevada
Posts: 2,459

Bikes: Catrike 700, Greenspeed GTO trike, , Linear LWB recumbent, Haluzak Horizon SWB recumbent, Balance 450 MTB, Cannondale SM800 Beast of the East

Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 399 Post(s)
Likes: 0
Liked 98 Times in 77 Posts
It is hard to compare lights that use discrete LEDs because you often don't know what type of LED is used in the light. Some LEDs are more efficient than others so will give you more lumens or a longer run time with the same capacity battery. Don't be afraid to try the Asian lights since many of the US brands are simply Chinese lights made in Chinese light makers branded with a US seller's name. The Blitzu Gator 320 light I received as a Christmas gift was made by Raypal, one of the largest Chinese bike light makers. It is sold without the Blitzu name for about half the price. How far a bike tail light can be seen is partly dependent upon the brightness but also on the area of the light that is lit. That's why I prefer a COB tail light because the light is evenly spread over a decent area. I'll PM you with some suggestions for lights I own.
VegasTriker is offline  
Old 09-30-17, 01:43 PM
  #3  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 25,230
Mentioned: 204 Post(s)
Tagged: 0 Thread(s)
Quoted: 13611 Post(s)
Liked 1,903 Times in 1,441 Posts
Also, keep in mind that mAh is a rating of amps over time. So, if you have two 4v batteries, one rated at 600 mAh, and the other at 650 mAh, then they may both have the same instantaneous power, and thus may have equal light intensities, but the one rated at 650 mAh will last longer (in theory). As far as long-term longevity, the rating doesn't mean a lot, although the higher Ah rating may mean it has a better buffer for a slow decline (or it could mean they took shortcuts, and the battery won't last as long).

Power = Watts = Volts x Amps (and power over time = watt hours).

So, if you have say a 4V battery, and an 8V battery pack with the same mAh rating, then the 8V pack will be able to put out more watts hours, and thus more overall power (over time).

The nice thing about rating in volts and Ah (1000 mAh = 1 Ah), is that it makes it easier to calculate the battery characteristics when building multi battery packs in serial and parallel. Serial connections increase volts, and parallel connections increase amps and amp hours.
CliffordK is online now  
Old 10-02-17, 09:30 AM
  #4  
Sal Bandini
Senior Member
 
Join Date: Mar 2017
Posts: 239

Bikes: 2017 Sirrus Sport

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 416 Post(s)
Liked 6 Times in 6 Posts
mAh is like gas tank in your car. It measures capacity.

Car A has 10 gallon tank. Car B has 15 gallon tank. Which car is better? Like your 2 lights you are considering, it depends.

You will not like notice big difference between 90 and 120 lumens, that's assuming they are accurately marked, which they probably are not.

I don't know what bike you are riding but assuming it's a nicer model, spend the extra $20 or so for quality light. That's chump change compared to cost of bike.
Sal Bandini is offline  
Old 10-02-17, 09:46 AM
  #5  
fietsbob
Banned
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 43,599

Bikes: 8

Mentioned: 197 Post(s)
Tagged: 0 Thread(s)
Quoted: 7607 Post(s)
Liked 1,315 Times in 826 Posts
Milli amp per hour is used to state battery capacity , but it can also be rate of drain by the demand end.
fietsbob is offline  
Old 10-02-17, 12:13 PM
  #6  
Iride01
Hits [ENTER] b4 thinking
 
Iride01's Avatar
 
Join Date: Jul 2017
Location: Mississippi
Posts: 7,107

Bikes: '20 Tarmac Disc Comp '91 Schwinn Paramount '78 Raleigh Competition GS

Mentioned: 31 Post(s)
Tagged: 0 Thread(s)
Quoted: 2773 Post(s)
Liked 1,396 Times in 1,020 Posts
Think of battery capacity as the gallons your cars fuel tank holds. The bigger the tank the more miles or time you get.

But when comparing different lights, it's just like comparing different cars. Bigger engines usually require bigger tanks.

So if the light manufacturer doesn't give you a chart or tell you how long the light will last in different modes, you cannot really compare them.

Nor can you use the battery capacity to compare brightness. Lumens or the outdated term candlepower is for that.

There may be generalizations you can make, but just like with cars. Some high performance ones get amazingly good mileage and attract everyone's attention too.
Iride01 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Cyclist3092345
Electronics, Lighting, & Gadgets
2
06-03-19 10:11 AM
DIY masochist
Electronics, Lighting, & Gadgets
19
12-02-18 07:33 AM
PastorJim
Electronics, Lighting, & Gadgets
20
10-30-18 11:25 AM
Dennis09
Electronics, Lighting, & Gadgets
1
09-18-18 02:44 PM
Raptor1956
Electronics, Lighting, & Gadgets
7
08-09-10 06:09 AM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.