Battery belts/packs: Lead-acid vs Ni-cad? at DVinfo.net

Collis Davis · September 5th, 2004, 05:42 AM

Hi,

I've been investigating getting a battery belt/pack to be used for various purposes: powering my ATW-101 wireless receiver and/or Canon XL1S camera or JVC Field monitor TM-910SU.

Various available adapters make these hookups possible. But the question is: What is the downside, if any, to purchasing the lead-acid type (usually $100 less than the the Ni-cad types)?

What's the useful life of these two types?

It seems that the lead-acid types pack greater amperage for the buck.

What's been the field's experience regarding these two battery types?

Many thanks from the Philippines.

Collis

Mike Rehmus · September 5th, 2004, 12:08 PM

The downside of lead-acid batteries is their voltage droop as they discharge. They can drop down to under 11 volts while still having a lot of stored energy. The other 3 main battery chemistries don't have this problem and maintaing their voltage far out on the discharge curve.

In practical terms, unless your gear runs on less than 12 volts it may turn off prematurely.

Sony made a 12 volt to 12 volt converter to sustain 12 volts out when the input volts dropped. They stopped making this device when NiCads and other battery technologies became main-stream.

Practical example. I tape 2-day exhibitions. Used to use an automobile battery to power 1 or 2 100 watt halogen lamps and my Sony EVW-300 camcorder. Somewhere about 2 hours into the first day, the camcorder would shut down due to low battery voltage and I'd have to go back to NP-1B batteries for it. The lead acid battery still had enough energy to run the lamps for all two days.

Now of course, with LiON batteries, I can run a PD150 almost all day on a single battery and run my 42-LED lamp for 2 full days on a single LiON pack.

Were I to replace my NRG battery belt cells, I'd change them from NiCad to NiMH and buy an appropriate charger. NiCads are just too heavy compared to NiMH or LiON and have other issues that may shorten their life.

Giroud Francois · September 5th, 2004, 12:46 PM

if your concern is money, lead is the best choice on short term.
You can even get on 3 elements of 6 V (=18V) and regulate to 12.
If you don't mind to transport heavy stuff....
On long term, lead is very weak, asking for continuous care.
Ni-cad is expensive , adds even more problems, so the value is not obvious versus the other technologies available (ni-mh and li-ion). If your expectations are high, lead and ni-cad does not fit anyway.
.

Collis Davis · September 5th, 2004, 05:47 PM

Mike & Giroud,

Thank you for your insightful comments on this question.

Mike, I had not really considered the NiMH or LiON types in my research, so will do so now.

Cheers,

Collis

September 5th, 2004, 05:42 AM	#1
Collis Davis Regular Crew Join Date: Dec 2003 Location: Metro Manila, Philippines Posts: 60	Battery belts/packs: Lead-acid vs Ni-cad? Hi, I've been investigating getting a battery belt/pack to be used for various purposes: powering my ATW-101 wireless receiver and/or Canon XL1S camera or JVC Field monitor TM-910SU. Various available adapters make these hookups possible. But the question is: What is the downside, if any, to purchasing the lead-acid type (usually $100 less than the the Ni-cad types)? What's the useful life of these two types? It seems that the lead-acid types pack greater amperage for the buck. What's been the field's experience regarding these two battery types? Many thanks from the Philippines. Collis __________________ Collis H. Davis, Jr. Okara Video Philippines

September 5th, 2004, 12:08 PM	#2
Mike Rehmus Wrangler Join Date: May 2002 Location: Vallejo, California Posts: 4,049	The downside of lead-acid batteries is their voltage droop as they discharge. They can drop down to under 11 volts while still having a lot of stored energy. The other 3 main battery chemistries don't have this problem and maintaing their voltage far out on the discharge curve. In practical terms, unless your gear runs on less than 12 volts it may turn off prematurely. Sony made a 12 volt to 12 volt converter to sustain 12 volts out when the input volts dropped. They stopped making this device when NiCads and other battery technologies became main-stream. Practical example. I tape 2-day exhibitions. Used to use an automobile battery to power 1 or 2 100 watt halogen lamps and my Sony EVW-300 camcorder. Somewhere about 2 hours into the first day, the camcorder would shut down due to low battery voltage and I'd have to go back to NP-1B batteries for it. The lead acid battery still had enough energy to run the lamps for all two days. Now of course, with LiON batteries, I can run a PD150 almost all day on a single battery and run my 42-LED lamp for 2 full days on a single LiON pack. Were I to replace my NRG battery belt cells, I'd change them from NiCad to NiMH and buy an appropriate charger. NiCads are just too heavy compared to NiMH or LiON and have other issues that may shorten their life. __________________ Mike Rehmus Hey, I can see the carrot at the end of the tunnel!

September 5th, 2004, 05:47 PM	#4
Collis Davis Regular Crew Join Date: Dec 2003 Location: Metro Manila, Philippines Posts: 60	Mike & Giroud, Thank you for your insightful comments on this question. Mike, I had not really considered the NiMH or LiON types in my research, so will do so now. Cheers, Collis __________________ Collis H. Davis, Jr. Okara Video Philippines

September 5th, 2004, 12:46 PM	#3
Giroud Francois Inner Circle Join Date: Feb 2004 Location: switzerland Posts: 2,133	if your concern is money, lead is the best choice on short term. You can even get on 3 elements of 6 V (=18V) and regulate to 12. If you don't mind to transport heavy stuff.... On long term, lead is very weak, asking for continuous care. Ni-cad is expensive , adds even more problems, so the value is not obvious versus the other technologies available (ni-mh and li-ion). If your expectations are high, lead and ni-cad does not fit anyway. .