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Battery Comparisons - June 1999

The graph below shows the discharge curves for the LiIon camcorder battery types NPF750 (Sony); HL530 (equivalent to Sony NPF550); and the Motorola NiMH 5087 currently in use in the CyberJacket.

The NPF750 550mA curve was obtained with a 10 ohm (plus ammeter) load - a lighter load than the CyberJacket, but greater than that presented by the ShoppingJacket/BlazerJet/CyberBag.  

The HL530 250mA and NiMH 200mA curves were both obtained with a 22ohm load.

The HL530 170mA curve was taken with a 32ohm load which gave a near identical power loading to the NiMH curve.

Typical loadings are shown in the table below.

 

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Two NPF750's connected in series were chosen to provide power for the ShoppingJacket/Blazerjet/CyberBag. These provide sufficient battery life to enable meaningful trials to be undertaken in a package which fits neatly into a jacket pocket.


NP-F750 Specification

Maximum Output Voltage : 8.4 V        Mean Output Voltage : 7.2 V        Capacity :     21.6 Wh

Dimensions : 38.4 x 39.8 x 70.8 mm    Mass : 200 g (7.1 oz)


CardPresso Load (with LocoMedia running)

  Eagle Bear
7.7v  (1xLiIon) 1,450mA 784mA
13v  (2xNiMH) 840mA 470mA
15.4v (2xLiIon) 705mA 395mA

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Last updated: January 14, 2000.
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