DOE Battery Charger Test Procedure Notice of 

Data Availability (NODA):

Applying the DOE Battery Charger Test Procedure to 

Multi-Voltage, Multi-Capacity and Multi-Voltage, MultiCapacity and Multi-Chemistry Battery Chargers

Final Report – May 9

th, 2014

Prepared by Navigant Consulting Inc. for the Department of Energy Building Technologies Program
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Disclaimer

This report was prepared as an account of work sponsored by an agency of the United States 

Government. Neither the United States Government, nor any agency thereof, nor any of their 

employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, 

express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or 

usefulness of any information, apparatus, product, or process disclosed, or represents that its use would 

not infringe privately owned rights. Reference herein to any specific commercial product, process, or 

service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply 

its endorsement, recommendation, or favoring by the United States Government or any agency, 

contractor or subcontractor thereof. The views and opinions of authors expressed herein do not 

necessarily state or reflect those of the United States Government or any agency thereof.
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Contents

1. Introduction ..........................................................................................................................................1

2. Test Procedure......................................................................................................................................1

3. Results and Discussion..........................................................................................................................2
Applying the DOE Battery Charger Test Procedure to Multi-Voltage, Multi-Capacity and Multi-Voltage, Multi-Capacity and Multi-Chemistry Battery Chargers Page 1 of 2

1. Introduction

As of February 2013, compliance with the California standards for battery chargers was required when 

distributing those products in California. To better understand the impact of these standards on the 

battery charger industry, DOE has been obtaining products from retail merchants and testing them in 

accordance with the DOE test procedure. This process has enabled DOE to examine the types of 

technologies manufacturers are employing to meet the California standards. 

While investigating these issues, DOE compared the results from its own testing activities to the publicly 

available energy efficiency ratings for the same units reported in the CEC database and found 

inconsistencies between these two separate sets of data. (The CEC database is available online at: 

http://www.appliances.energy.ca.gov/). Because the values obtained through DOE testing and the 

values reported to CEC should have been obtained through use of the same test procedure (found in 

Appendix Y to subpart B of 10 CFR Part 430), these inconsistencies have raised a question as to whether 

these differences have arisen from an ambiguity in the DOE test procedure. 

2. Test Procedure

DOE tested each unit according to the Battery Charger Test Procedure published in June 2011. Two of 

the units that DOE tested were capable of charging either multiple batteries at different voltages and 

capacities or charging batteries of different chemistries as well as different voltages and capacities. 

Batteries were selected for these units per the DOE test procedure, Table 4.1 “Battery Selection for 

Testing” which indicates that for a battery charger that is multi-voltage and multi-capacity a total of 3 

tests are to be performed. Those tests included the following:

1. Of the batteries with the lowest voltage, use the one with the lowest charge capacity. Use only 

one port. [BATTERY 1]

2. Of the batteries with the highest voltage, use the one with the lowest charge capacity. Use only 

one port. [BATTERY 2]

3. Use all ports and use the battery or the configuration of batteries with the highest total rated 

energy capacity. [BATTERY 3]
Applying the DOE Battery Charger Test Procedure to Multi-Voltage, Multi-Capacity and Multi-Voltage, Multi-Capacity and Multi-Chemistry Battery Chargers Page 2 of 2

3. Results and Discussion

Unit 1- Multi-Voltage, Multi-Capacity, Multi-Chemistry Battery Charger

Publicly Available Data:

Battery Selected E24 (Wh) Pm (W) Psb (W) BE(Wh)

Unidentified 24.26 0.44 0.19 26.971

DOE Test Data:

Battery Selected E24 (Wh) Pm (W) Psb (W) BE (Wh)

Battery 1 (NiCd) 39.56 1.01 0.59 8.68

Battery 2 (NiCd) 70.37 0.62 0.59 28.77

Battery 3 (NiCd) 88.44 4.45 0.59 38.08

Battery 3 (LiIon) 50.91 0.8 0.59 38.47

Additional 

Battery A2(NiCd)

64 3.03 0.59 23.73

Additional 

Battery B2(NiCd)

69.87 3.76 0.59 28.89

Unit 2 – Multi-Voltage, Multi-Capacity Battery Charger

Publicly Available Data:

Battery Selected E24 (Wh) Pm (W) Psb (W) BE (Wh)

Unidentified 88.11 0.41 0.31 54.00

DOE Test Data:

Battery Selected E24 (Wh) Pm (W) Psb (W) BE (W)

Battery 1 66.03 2.17 0.88 9.87

Battery 2/33152.69 3.69 0.88 50.24

 

1

The battery energy test in the DOE test procedure measures the energy, in watt hours, discharged by the battery. The 24-

hour test measures the amount of energy used to fully charge a completely discharged battery and maintain the battery over a 

period of at least 24 hours. It is technically infeasible for the battery energy to be greater than the 24-hour energy because 

that would mean that an energy conversion rate of greater than 100% was achieved. DOE found that this was the case for over 

1% (99/9803 as of 5/1/2014) of the data reported in the CEC database. 

2

Further testing was completed than is required by the test procedure in an attempt to replicate published results. DOE could 

not replicate published results with any of the batteries that were tested.

3

For this unit the same battery represents both the battery with the highest voltage and lowest charge capacity, as well as, the 

highest voltage and highest total rated energy capacity. In this case only 2 tests were completed, per the battery selection 

criteria.