The best replacement for nimh is nicd.

The best alternatives to nimh are rated as following:
★★★★★  nicd
★★★★  lithium
★★★★  lipo
★★★★  nicad
★★★  alkaline
★★★  lithium ion
★★  lithium batteries
★★  li ion
★★  li-ion
★★  mah
★  nicd batteries
★  lithium aa batteries
★  nicd rechargeable batteries
★  mah batteries
★  lipo airsoft
★  lead acid
★  nicd airsoft
★  nicd charging
  nicd which is better
  nizn
  lipo batteries
  nicd rc
  alkaline batteries
  nicad batteries
  lithium polymer
  li po
  nicad battery
  lithium-ion batteries
  li-ion battery
  lipo rc
  nicd charger
  lifepo4
  7.4 lipo
  nicd batteries which is better
  ni-cd
  sla
  lithium ion batteries
  rnli
  li poly
  li ion battery
  lipo runtime
  ni cad
  lithium battery

Your alternative for nimh is not listed? Suggest!
Speaking about nimh, one probably shouldn't forget about brushless.

Other search terms related to nimh and their ratings are:
★★★★★ brushless
★★★ nicad charger
★★ lipo charger
★ nicd
You have in mind a companion for nimh and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of nimh in all years. Click on graph for more.
nimh
nicd
lithium