Who offers the best Nimh batteries?

[Al Lewis]

You can also get a good deal here.

http://www.all-battery.com/6vnimhbatterypackseries.aspx

[jack strickland]

	Quote: Originally Posted by dick hanson
	Jack- the Eneloop simply are not designed for high current spikes or loads They were developed for cameras or similar uses ,where long shelf life with low discharge and stable long use in low current devices is intended if yo look at the mfgrs spec page on them, you will see that they are high impedance designs I use em for my Canon and tx apps. Absolutely great in those apps. If you test using a WHATTMETER ,the voltage depression und high load is obvious. In a model such as slow flying glider -using small, low demand servos -they also would work well.

Dick This is the first time a WATTMETER has come up regarding battery checking. If Ohms law serves me correctly, an amp meter would serve to do the watt calculation. Where is everyone getting this high internal restance info from??? I sent an email to Sanyo, asking for the spec. on the internal restance. Will post the results.

[dick hanson]

I read the published SANYO specs on the batts - they are as noted above
anyway the WHATTMETER setyp really give a fast readout o what is happening under load
Thedisplay shows volts from source
Then
as th load is applied , it displays amps (the load) and the amount of voltage depression caused by the load.
The watts being displayed now lets you see the entire picture (amps x voltage) which is occurring.
This is where it is relatively easy to get fooled
The volts MUST be measured under the operating load ..
Some fliers blame the rx for quitting because a quck check after a crash shows "good voltage"
-which is a meaningless test.

The radios -up until to the 2.4 types, would operate at extremely low voltag levels and servo powe simply diminished as load depressed the power supply (actual voltage under load). Some flyers really never noticed th diminished servo power
2.4 type radios ALL have a minimum operating theshhold typically somewhere under 4 volts (4-3 volts).
The servos we now all seem to use ,swill whatever they can get, like a sailor on leave.
To get what you paid for ---- you need batts -wires - switching devices (regs n motor speed controls etc,. which-will keep up with the demand (amp/volt load) of the servos.
It is all pretty straightforward factfinding, .
I got it all to make sense when I was trying to determine the best setups for litle electric motors for small models. Note in the second picture- the meter shows actual volts amps and watts required to provide 7 ounces of thrust .
Some of the batteries I tried sjowed an instant voltage drop of over 1/2 starting voltage - as soon as the motor started.
Note: the battery pack was 12.5 volts before the load was applied.
The present LiPos and A123 cells will accept incredible loads with minimal voltage drop
The new problem is that any short circuit using these high output cells can fry all the wires -in a heartbeat
Ask me how I know that one ---

[jack strickland]

Will all you fellows please tell me where you get your info about the enloop cells? Is it indeed factual or heresay? I have contacted Sanyo customer support about the specs about the enloop cells, got the tech sheet for them, which is enclosed. This agent said we cannot talk to any Sanyo engineers. He also stated that if the cells are performing ok, not to be concerned about internal resistance. It would appear to be logical the internal r is about the same as other Sanyo nmih cells. I would appreciate any factual information any of you can provide. Ths spec sheet will follow in the next post.

Jack

[jack strickland]

1900mAh
1.2V
Fast Charge

2) 2000mA × 1.1h
Charge
Condition Fast Charge 2) 0°C - 40°C
0°C - 50°C
Less than
90days -20°C - 40°C
Less than
1year -20°C - 30°C
Approx. 25mΩ(at 1000Hz)
Approx.27g
14.35(D) x 50.4(H) mm

Typical Characteristics

Charge Discharge

2007/08*

Dimensions
(with tube)

Specifications

Cell Type HR-3UTG

Charge : 200mA×16h, Discharge : 400mA(E.V.=1.0V) at 25°C
Nominal Voltage
Discharge Condition
Size

4) Diameter) x (Height)
Type : Nickel-Metal Hydride Battery
D
H
14.35 mm
50.4 mm
Internal Impedance 3)

(after discharge to E.V.=1.0V)
Weight

4)

Charging Current x Time
2)Use recommended charging system.
3)After a few charge and discharge cycles under the above 1) condition.
4)With tube.
1)Single cell capacity under the following condition.
50.4 mm
14.35 mm

Capacity 1)

[rcakropilot]

	Quote: Originally Posted by dick hanson
	The present LiPos and A123 cells will accept incredible loads with minimal voltage drop The new problem is that any short circuit using these high output cells can fry all the wires -in a heartbeat Ask me how I know that one ---

Is short circuting a major issue with A123's? I use them on my 35% Extra, Love 'em. Know lots of guys using them and haven't heard one complaint.

Fill me in.

[Judge]

	Quote: Originally Posted by jack strickland
	Will all you fellows please tell me where you get your info about the enloop cells?

See post #30 above: http://www.flyinggiants.com/forums/f...tml#post944388

I posted the actual Sanyo spec sheet.

[racefreak2002]

Well for what it's worth here is one for HANHTIME HOBBIES. one month ago I had a lipo fire inside my plane. cooked most all electronics. purchaced a new airframe and was told I should contact HANGTIME HOBBIES for all new 123 setup. I'M talking batteries, switches, charger . the whole setup. so here is the real kicker. I e- mailed steve at HANGTIME HOBBIES for some help selecting ALL of my battery needs. After waiting a week I got no response. so, I thougth ok I would give him a few days and i will get some help. after RE E-MAILING my request again; another week went buy and finally guess what? NO RESPONSEso here is my evaluation. screw :24: HANGTIME HOBBIES and his battery factory. this is why there is no pretty secretary or telephone number. REMEMBER guys, his website says the best way to contact him is by E-MAIL BUYER BEWARE!!!!!!!!!!!!!!!!!!!!!! THERE IS OTHER PLACES TO PURCHACE PRODUCT!!!!!!!! THANK'S STEVE!!!!! WORKS BOTH WAYS!!!!!!

[f5air]

omg who charge lipos inside and airplane??????? its like play russian roulette. I have seen the expensive $200 bucks lipo brand fire..... so its not something that depends of the brand.
I have got some products from hangtimes and i got really nice service and super fast shipping.

[racefreak2002]

I will agree that I,WE, tend to get somewhat lazy about li-po volitality. that was my fault. also I

am GREATFULL that it happened at the field rather than in my shop. after hundreds of charge cycles I think that we become forgetfull about these dynomite packs. this is why I wanted to change technology to A 123. I'TS NOT my fault for trying to contact HANGTIME HOBBIES for product. I will not negitavely comment on his knowledg or his product . I can only comment on his lack of NOT responding to a new customer. I was not thinking about 123 technology or comparing HANGTIME HOBBIES to another competitor. I was going to purchase my entire setup for sure.

I think that when a customer's questions are TOTALLY IGNORED for one month that a 100% true statement is not out of place. I just have choosen another place for product. why wait for someone to NOT help you select some of THEIR product!!!!!

[Mokken]

	Quote: Originally Posted by rcakropilot
	Is short circuting a major issue with A123's? I use them on my 35% Extra, Love 'em. Know lots of guys using them and haven't heard one complaint. Fill me in.

Not had any problems with the 12 packs I'm running. But they are all in gas airplanes, I know Dick does some pretty wild electric plane setups, so maybe he's referring to those.

[T. Bob]

What is Nimh?

Really I don't get it

Is this some sort of joke?

[jack strickland]

	Quote: Originally Posted by Judge
	See post #30 above: http://www.flyinggiants.com/forums/f...tml#post944388 I posted the actual Sanyo spec sheet.

Here is the latest info I have for the enloop packs in my plane. You fellows are right, the cells do not perform well on the new digital servos. I have a new Airtronics 94780 on the rudder, and after a flight using a lot of rudder (forgot to hook up ailerons after repair) the pack discharged to 1060 ma. that was on the rudder servo. The other pack which was on the other non high drain servos discharged at 1680 ma. All this was on 30 minutes of flying total. So to sum up, The enloops will work ok ,for what everyone is calling analog servos, which they are not! don't know how this got started. So -the packs for the 2 receivers will be replaced with 1700 scr ni-cads. Thanks for the response.
Regards to all

[dick hanson]

	Quote: Originally Posted by T. Bob
	What is Nimh? Really I don't get it Is this some sort of joke?

NIMH
National Institute of Mental Health

Either support our efforts or we will snuff you.

[dick hanson]

	Quote: Originally Posted by jack strickland
	Here is the latest info I have for the enloop packs in my plane. You fellows are right, the cells do not perform well on the new digital servos. I have a new Airtronics 94780 on the rudder, and after a flight using a lot of rudder (forgot to hook up ailerons after repair) the pack discharged to 1060 ma. that was on the rudder servo. The other pack which was on the other non high drain servos discharged at 1680 ma. All this was on 30 minutes of flying total. So to sum up, The enloops will work ok ,for what everyone is calling analog servos, which they are not! don't know how this got started. So -the packs for the 2 receivers will be replaced with 1700 scr ni-cads. Thanks for the response. Regards to all

You are not the only one to get caught on the fine points of all the new battery types
I am a great fan of Eneloops and A123 cells

I also still use NIMH and Lipos - each has it's own place in the scheme of things.
Those 1700 nicads may be all you need
My own taste is to susbstite a A123 wherever higher , instant loads are encountered
and use Eneloops when constant low loads (a TX is a perfect example ) are encountered.
For blasts o power in small light planes - I use the latest LiPos- but I still am wary of these instant fire source devices.