Rechargable batteries and LED light

[SilverFox]

Hello Dabigkahuna,

Welcome to CPF.

I use a Vanson charger and have been pleased with its performance.

The only problem comes when charging high capacity D cells. The charger has a timer shut off that will stop the charge before the cells are completely charged. My work around is to unplug the charger half way through the charge cycle. This resets the clock and the cells completely charge. By the way, I am referring to 9500 mAh D cells. It has no problems with AAA, AA, or C cells (so far until their capacity reaches that level...).

NiMh chemistry has a self discharge rate of about 1% per day. This means that if you let the batteries set on a shelf they would end up at about 30% of full charge in 120 days. The self discharge rate varies as the cell ages, so this is just a rough guideline. I suggest recharging NiMh cells at least every 6 months. Most people recharge their cells more frequently.

Tom

 

[Blikbok]

dabigkahuna:

I am another proud owner of the Maha 401-S. It's a great charger for AA and AAA. It stops when the cells are full-- the indicator turns from red (charging) to green (done). There is a self-discharge on NiMH of about 1% of total capacity per day, so I'd top off the cells before you use them.

The latest and highest capacity cells are the least cost-effective (600 mAh/$). The sweet spot right now is between 2100-2000 (~900 mAh/$). Also, the high end is the location of a lot of competition, and a lot of...exaggeration.

I can't believe we've gotten this far without a reference to:
http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM

If you check the actual capacity to claimed capacity, Maha and Sanyo are usually within 5%. Notice how even the worst NiMH has twice the runtime of the best alkaline.

I have a few 2000 cells, but mostly run 1700 because when I bought them, they were the price/performance winners.

A Maha 401-S and Maha cells won't be a bad investment.

 

[3rd_shift]

What about this one here? /ubbthreads/images/graemlins/icon3.gif

I have had great luck with these over the last several months now. /ubbthreads/images/graemlins/happy14.gif
These only stop when the batteries actually are full, regardless of thier capacity.
High capacity AA nimhs are fully charged in about 4-5 hours depending on thier capacity.
This charger also accurately tops off partially discharged batteries in even shorter time.
Same true for AAA's.
Each channel is fully independent and can charge any size battery of either chemistry at the same time in the same unit. /ubbthreads/images/graemlins/happy14.gif
It sure does look an awful lot like the accucharger20 doesn't it? /ubbthreads/images/graemlins/icon3.gif
I would say just get 2 of these, 1 for each set of your batteries. /ubbthreads/images/graemlins/smile.gif
By the way, Nimh batteries have a fairly steady discharge and will keep your led bike lights nice and bright for a while.

How long are your night time rides anyways?

I have also had good luck with the Nexcell AA batteries living up to thier mah ratings with good reliability.

I have lost 1 AAA Nexcell to a fast 1 hour charger.
(it bleed to death there) /ubbthreads/images/graemlins/eeew.gif
I have also had a D cell Nexcell quit taking a charge after it had already gone through 50+ recharges.

 

[Doug Owen]

[ QUOTE ]
dabigkahuna said:
[ QUOTE ]
Doug Owen said:
Probably the most recommended AA/AAA charger is the MAHA 401, at about $40. Fast, safe, small, cool running, well respected, can be run on 12 Volts DC.

I've owned one for several years now, and can recommend it highly. I bought mine from Thomas Distributing . There are some attractive package deals with 2300 mAh cells that might interest you, they too are to be recommended.

Doug Owen

[/ QUOTE ]

This would be the MH-C401FS?

One thing about any charger. I have found info about one or another only being able to charge to a given level which, I assume, would mean if you had one that would charge to 2000, then you wouldn't get the full benefit of a 2300 mAh.

Do any of these charges measure the capacity and adjust accordingly so that if later we get, say, a 2500 mAh battery, it would still fully charge it?

[/ QUOTE ]

Yes, that's the current model. It fully charges cells, it detects the end of charge, so you can put partially charged cells in anytime and 'top them up'. No matter what capacity.

Doug Owen

 

[cypher2001]

With the MH-C204f charger (atleast the old one) there was an issue with fully charged batteries. This might apply to the other charges as well.

Putting in a fully charged battery would force it into another charge cycle. The same was said for a power interruption when the cells were in a trickle charge state. Here is the text from the website:

-----------------------------------------------------------
The MH-C204F is a "smart" charger and it uses a technique called Negative Delta Voltage sensing that senses a brief drop in voltage when batteries become fully charged. This method is generally capacity independent and works for most types of capacity.

However if the batteries have already been fully charged and you place your batteries into MH-204F charger, the charger will again start to charge your batteries all over again. Only this time the charger will be unable to detect the negative voltage drop ( since your batteries are actually fully charged already ) and will probably cause damage to your batteries, charger or both.

 

[Blikbok]

My 401-S will accept a full cell and turn the LED green in less than a minute, so I don't think it has the same issue as the 204.

But I find it hard to believe that a charger would pay attention to the Delta V and not the absolute V, which would be 1.4-1.5 V at full capacity.

I passed on the 204 because it has only two banks of two instead of the 401's four banks of one.

 

[dabigkahuna]

[ QUOTE ]
3rd_shift said:
What about this one here? /ubbthreads/images/graemlins/icon3.gif

I have had great luck with these over the last several months now. /ubbthreads/images/graemlins/happy14.gif

How long are your night time rides anyways?


[/ QUOTE ]

Boy, lots of posts to analyze, but let me respond to this first.

My typical ride is 50-90 minutes in the dark. On occasion, if I don't stop at the beach for breakfast (I ride to Waikiki) and just come right back home, add another hour or so. Obviously, this should be well within any rechargable battery's capability, but I still would prefer not to have to take the light apart to recharge the batteries any more than necessary.

 

[koala]

If you think removing the rechargeable batteries and loading them is troublesome then nicd has pretty low self discharge rate, next to lithium cells. However, convenience always link to extra $$$. So it's your call.

For those who work during the normal hours find it hard to get out during the day time. I cycle after dinner(no digestion problem!), ride 3-4 times per week depending on the weather. Every ride is 2-3 hours. My illumination is a Surefire KL1(R2K modded) dutchtaped to my handle bar. Anyone who owns a KL1/ARC LS know the ability of the light. It's a good bike light for mountainbiking and also road traffic up to 45kmh/28mph. Any faster I need brighter source of light to scan my path.

I have no problems with the road traffic when aimed properly. It's visible from far away and the optic in KL1 has a good flood properties so incoming cars can see you pretty well. The powersource is a 3.6v 17670 Lithium Ion cell. IMHO pretty limited runtime. 4x 2300mah AA could do better but we are talking about size now. I have to say this... my Luxeon just leave other bikers wonder and motorist staring at me. Before they ask the FAQ, I say "No, it's not HID".

ps, if your thinking of dutchtape, don't leave your bike parked outside. You will be going home in darkness.

Vince.

 

[paulr]

How long is your ride? Maybe you want to skip all this battery removal stuff and get a handlebar mount for a rechargeable light like a Streamlight Strion. You don't have to take the batteries out of the flashlight to charge it. You just plop the whole light into a charging stand the way you'd charge a cell phone. Presumably you want your light easily removable anyway, so you can take it off the bike when you park it outside somewhere, to prevent the light from getting stolen by some thief with a screwdriver.

 

[dabigkahuna]

[ QUOTE ]
koala said:
For those who work during the normal hours find it hard to get out during the day time. I cycle after dinner(no digestion problem!), ride 3-4 times per week depending on the weather. Every ride is 2-3 hours. My illumination is a Surefire KL1(R2K modded) dutchtaped to my handle bar.

[/ QUOTE ]

Well, I'm retired, though I do some part-time work. I ride early (3:30 AM) simply to avoid some serious traffic issues on the way to Waikiki. After I eat breakfast at the beach, I ride back home (traffic is not as bad going that direction). While at the restaurant, the bike is locked to a palm tree, where I can see it.

But I don't think I want to deal with duct tape. Seems there should be some sort of generic mount that would let people handle such things, but maybe not.

I use a Cateye Opticube (5 led) now, which seems to be the best bang for the buck I've found. I wouldn't say it is good for 28 mph though! Fortunately, most of my route has street lights and the worst place for light is also going up a big hill so I'm not going fast anyway. But I wouldn't mind better light. On occasion, street lights are not working (even several in a row).

 

[dabigkahuna]

[ QUOTE ]
paulr said:
How long is your ride? Maybe you want to skip all this battery removal stuff and get a handlebar mount for a rechargeable light like a Streamlight Strion. You don't have to take the batteries out of the flashlight to charge it. You just plop the whole light into a charging stand the way you'd charge a cell phone. Presumably you want your light easily removable anyway, so you can take it off the bike when you park it outside somewhere, to prevent the light from getting stolen by some thief with a screwdriver.

[/ QUOTE ]

My light has a quick release, but even so, I prefer not to have to take the time to change batteries any more than necessary. It's just a personal irritation.

I wonder how well the light you mention illuminates compared to my "official" bike light? You do need a fair amount of illumination at a distance when riding.

Oh, my ride is usually 45-90 minutes, but sometimes a couple hours. It is also possible that on rare occasions, I'd need light for as long as 4 hours (VERY rarely).